Family Dynamics and Young Adults’ Well-Being: The Mediating Role of Sibling Bullying

Abstract

Although a common form of family violence, sibling bullying is often viewed as harmless by families and society. Consequently, it has not received as much attention in research compared with peer bullying or other types of family violence, such as interpartner violence, child abuse, and elder abuse. Considering that sibling relationships have lasting effects on children’s development, this retrospective study focused on the antecedents and outcomes of sibling bullying. Grounded in family system theory and social learning theory, it explored whether sibling bullying during childhood and adolescence mediated the relationship between negative family dynamics (i.e., sibling rivalry, interparental hostility, and parental hostility) and young adults’ well-being (i.e., sense of competence, internalized problems, self-esteem, and satisfaction with life). Data from 216 respondents were analyzed using structural equation modeling. Results revealed that young adults who reported higher levels of sibling rivalry and interparental hostility were more likely to be victims of sibling bullying. In turn, sibling bullying was associated with lower sense of competence, self-esteem, and life satisfaction, as well as more internalized problems. Parents’ hostile behaviors toward their children were not associated with sibling bullying but were negatively associated with well-being in early adulthood. Our work underlines the importance of harmonious family dynamics and the need for sibling bullying to be taken more seriously by parents and family members. From a clinical point of view, our findings suggest that clinicians and human service workers should adopt a family-level approach when trying to reduce sibling bullying and its negative outcomes by educating parents about the interdependence of family relationships.

Keywords

family dynamics sibling bullying well-being young adults

Sibling bullying is a type of aggressive behavior among siblings that is repeated over time, intended both to cause harm and to dominate (Bowes, Wolke, Joinson, Lereya, & Lewis, 2014). It includes emotional, physical, and verbal aggressive behaviors (Hoetger, Hazen, & Brank, 2015; Tanrikulu & Campbell, 2015). Sibling bullying has been reported to be the most commonly occurring form of family violence (Ensor, Marks, Jacobs, & Hughes, 2010; Mathis & Mueller, 2015; Tippett & Wolke, 2015), and one of the most frequent types of aggression in society in general (Skinner & Kowalski, 2013). Yet, it is often viewed as harmless by parents and society (Pickering & Sanders, 2017). Some authors even specified that sibling bullying is not only accepted among family members but also expected and sometimes considered as being potentially beneficial for children’s development (Skinner & Kowalski, 2013; Tucker & Kazura, 2013). In the scientific literature, it has not received as much attention compared with peer bullying or other types of family violence, such as interpartner violence, child abuse, and elder abuse. Kiselica and Morrill-Richards (2007) even identified sibling bullying as a “forgotten abuse.” However, a growing body of research conducted in the last decade has revealed evidence of negative concurrent and long-term outcomes of sibling bullying, such as greater mental health distress, as well as lower social competence and self-worth (Bowes et al., 2014; Buist & Vermande, 2014; Tucker, Finkelhor, Turner, & Shattuck, 2013).

Considering that sibling bullying is a neglected issue despite its pervasiveness at home and its potential concurrent and long-term negative effects (Tanrikulu & Campbell, 2015), the aim of the current study is to acquire information about its risk factors and its adverse effects on well-being. More precisely, the objective of the current retrospective study is to examine whether and how sibling bullying during childhood and adolescence mediates the relationship between family dynamics and young adults’ well-being. By documenting the complexity of sibling bullying, our hope is that the current study will serve as an impetus for greater efforts to address the problem.

Sibling Bullying

Sibling bullying has been defined as aggressive behaviors between brothers and sisters (e.g., hitting, throwing objects, name-calling, hostile arguing) that are repeated over time to cause harm and to dominate (Bowes et al., 2014; Menesini, Camodeca, & Nocentini, 2010; Monks et al., 2009; Skinner & Kowalski, 2013). Researchers have used different terms to describe these aggressive sibling interactions, such as bullying, aggression, violence, or abuse (Tippett & Wolke, 2015). Thus, studies on aggressive sibling interactions often included behaviors that fit the definition of bullying, but were not labeled this way by the authors (Hoetger et al., 2015). For a matter of simplicity, we used the term sibling bullying throughout the article when the concept measured by the other researchers corresponded to the definition of sibling bullying presented above (Hoetger et al., 2015; Monks et al., 2009).

Findings converge to indicate that sibling bullying is far more common than peer bullying (Hoetger et al., 2015; Johnson et al., 2015; Skinner & Kowalski, 2013; Tanrikulu & Campbell, 2015). The prevalence of sibling bullying during childhood varies between studies ranging from 30% (Duncan, 1999) to 78% (Skinner & Kowalski, 2013). In contrast, 10% to 33% of students reported having experienced bullying at school (Hymel & Swearer, 2015). Despite the prevalence of sibling bullying, Kiselica and Morrill-Richards (2007) indicated that it is less likely to be reported outside the family than peer bullying. Researchers argued that the lack of reporting outside the home is part of the reason why sibling bullying has received far less attention from researchers and practitioners than peer bullying (Hoetger et al., 2015).

Sibling bullying seems to take place for different reasons than peer bullying, and the relation between the victim and the perpetrator varies remarkably from one type of bullying to the other (Skinner & Kowalski, 2013). For instance, it is easier for siblings, compared with peers, to provoke or upset one another by exploiting the other’s weaknesses due to the amount of time siblings spend together and how well they know each other (Ensor et al., 2010; Tippett & Wolke, 2015). Thus, by comparison with peer bullying, perpetration and victimization through sibling bullying are more strongly related, indicating an almost reciprocal dimension to sibling bullying (Mathis & Mueller, 2015; Skinner & Kowalski, 2013; Tippett & Wolke, 2015). This reciprocal dimension makes the imbalance of power, an important criterion to identify peer bullying, less central in sibling bullying. The differences between the two types of bullying (i.e., peer bulling vs. sibling bullying) limit the generalizability of the findings of the peer bullying literature to family violence. This supports the need for studies that aim to shed light on the risk factors and negative outcomes of sibling bullying.

Sibling Bullying and Negative Outcomes

Monks and colleagues (2009) stressed that the paucity of studies on sibling bullying is surprising considering that the sibling relationship is considered one of the key influences on children’s development (Buist & Vermande, 2014; Duncan, 1999; McHale, Updegraff, & Whiteman, 2012; Tanrikulu & Campbell, 2015; Tucker, Cox, et al., 2013; Tucker, Finkelhor, Turner, & Shattuck, 2014). Researchers have documented time and time again the benefits of close sibling relationships (Pike, Coldwell, & Dunn, 2005; Richmond, Stocker, & Rienks, 2005) and the negative outcomes of destructive sibling relationships (Button & Gealt, 2010; Garcia, Shaw, Winslow, & Yaggi, 2000; Graham-Bermann, Cutler, Litzenberger, & Schwartz, 1994; Stocker, Burwell, & Briggs, 2002). More precisely, a meta-analysis on child relationship quality showed that more warmth and less conflict between siblings are associated with less internalized and externalized problems (Buist, Deković, & Prinzie, 2013).

The available literature on sibling bullying is in line with these findings. Studies have linked sibling bullying to poorer mental and physical health, as well as to lower academic and social competence (Buist & Vermande, 2014; Duncan, 1999; Mathis & Mueller, 2015; Tucker, Finkelhor, Turner, & Shattuck, 2013; Tucker, Van Gundy, Sharp, & Rebellon, 2015; Wiehe, 1997). Bowes and colleagues’ (2014) findings also revealed that emerging adults who were victims of sibling bullying during childhood were twice as likely to develop depression and to report self-harming compared with individuals who indicated that they were never bullied by a sibling. Similarly, respondents who were asked how they felt their childhood sibling abuse affected them as adults referred to poor self-esteem, as well as feelings of inferiority, inadequacy, and worthlessness (Wiehe, 1997).

Family Dynamics and Sibling Bullying

The factors influencing sibling bullying are diverse, and researchers have argued that parents’ behaviors are among the most important ones (Wolke, Tippett, & Dantchev, 2015). Research in this area has been primarily guided by two theoretical approaches: the family system theory (Cox & Paley, 1997, 2003; Minuchin, 1988) and the social learning theory (Bandura, 1978). The family system theory postulates that family members are interdependent and continuously exert a mutual influence on one another, whereas the social learning theory posits that children can learn aggressive behavior patterns either directly through experience or indirectly by observing people around them. Empirical findings support both theoretical approaches (Tippett & Wolke, 2015; Tucker et al., 2014). More precisely, results have suggested that high levels of conflict between family members increase the risk of sibling bullying (Bowes et al., 2014; Menesini et al., 2010; Tippett & Wolke, 2015; Tucker et al., 2014). Both parents’ interactions with their children and with one another influence the incidence of sibling bullying. Specifically, negative parenting behaviors, such as shouting, quarreling, and hitting, and greater exposure to interparental conflict were strongly associated with sibling bullying (Bowes et al., 2014; Hoffman, Kiecolt, & Edwards, 2005; Tippett & Wolke, 2015; Tucker et al., 2014; Wolke et al., 2015). Sibling rivalry was also linked to higher levels of sibling aggression (Tucker, Cox et al., 2013). In this regard, many theorists “point to sibling rivalry as a root of sibling conflict” (Whiteman, McHale, & Soli, 2011, p. 129).

These results highlight the crucial role of family dynamics in sibling relationships and the need to further explore these issues in the context of sibling bullying. Although Tucker and colleagues (2014) have examined the influence of family dynamics during childhood for sibling bullying, family dynamics, sibling bullying, and well-being have yet to be studied simultaneously. Testing the influence of family dynamics during childhood (or adolescence) on sibling bullying and young adults’ psychological well-being is an important next step in the literature of sibling bullying, as it will add to the existing knowledge about the role of family dynamics on well-being later in life.

The Current Study

The objective of the current retrospective study is to bridge the gap in the literature by examining whether sibling bullying victimization mediates the relationship between family dynamics and young adults’ current well-being. Because children and adolescents are similarly affected by many forms of sibling aggression (Tucker, Finkelhor, Shattuck, & Turner, 2013), we chose to focus on young adults’ recalled experiences of sibling bullying during childhood and adolescence. In this study, family dynamics were operationalized by sibling rivalry, interparental hostility, and parental hostility, whereas well-being was operationalized by levels of sense of competence, internalized problems, self-esteem, and satisfaction with life. These indicators of family dynamics and of well-being were selected on account of their significance in the fields of family psychology, family violence, and developmental psychology. In accordance with the family system theory, the social learning theory, and previous research (Bowes et al., 2014; Buist & Vermande, 2014; Mathis & Mueller, 2015; McHale, Updegraff, Jackson-Newsom, Tucker, & Crouter, 2000; Tippett & Wolke, 2015; Tucker, Finkelhor, Turner, & Shattuck, 2013), we expected that negative family dynamics would be associated with more experiences of sibling bullying, which in turn would be negatively associated with young adults’ well-being.

Method

Participants

The participants in this study were 244 French–Canadian young adult university students. Twenty individuals were excluded from all analyses because they had not reported their gender, their number of siblings, or their birth order. Furthermore, respondents who did not complete all the questionnaires or who failed to answer more than 80% of the items in a questionnaire were also excluded (n = 8) from all analyses, leaving a final sample of 216 individuals. The remaining participants (44 males and 172 females) were living in New Brunswick and their mean age was 19.01 years (minimum = 17, maximum = 33, SD = 2.01). Participants were predominantly Caucasian and 65% were undergraduate first-year university students (M = 1.70 completed university years, SD = 1.26). On average, they had 1.81 siblings (SD = 1.53) and were mostly the first-born (45% of the sample) or second-born (39% of the sample) child. Fifty-five percent of the participants were still living in the parental home. The vast majority of participants (69% of the sample) lived in a family of origin with two parents in a first marriage, 7% had parents who cohabited together without being married, 3% reported the death of one parent (mostly during their adolescence or adulthood), and 20% had parents who were divorced/separated (mostly during childhood). Almost half (47%) of the respondents in non-intact families revealed that they lived in a blended family following their parents’ divorce or separation. The highest level of education most commonly completed by mothers and fathers was an associate’s degree (33% and 40%, respectively).

Procedure

Prior to conducting the research, a certification of compliance with ethical principles was obtained from the institutional research ethics board of the university at which the research was done. The research was conducted in accordance with the approved protocol. The following criteria were used to select participants for the current study to form a convenience sample: having at least one sibling and being able to report on one’s experience with both parents in the family of origin. Participants were recruited via announcements in lectures in many departments of a Canadian university. Participants were informed that they would be participating in a study on family dynamics during their childhood and adolescent years and on their current psychological functioning. This study was not about the current situation at home, as sibling bullying tends to diminish with age (Finkelhor, Turner, & Ormrod, 2006; Tanrikulu & Campbell, 2015; Tucker, Finkelhor, Shattuck, & Turner, 2013). Participants first consented and then completed the questionnaires (in French) measuring demographic variables, sibling rivalry, interparental hostility, parental hostility, sibling bullying, sense of competence, internalized problems, self-esteem, and life satisfaction.

Measures

Demographic variables and characteristics of the family of origin

Participants provided relevant background data, such as their age, number of siblings, and birth order. Participants were also asked to report their parents’ current marital status and educational levels.

Family dynamics

Sibling rivalry

We used the rivalry scale of the Sibling Relationship Inventory developed by Stocker and McHale (1992; Perlmutter, Touliatos, & Holden, 2001) to measure sibling rivalry. The four-item scale assessed respondents’ belief that their parents treated them unfairly and inequitably in comparison with the treatment of their siblings (e.g., “Many kids complain that their mothers aren’t fair about how they treat them compared to how they treat their brothers and sisters. How often did you feel that your mother treated your siblings better than she treated you?”; “How about with your father? How often did you think that he treated your siblings better than he treated you?”). Items were answered using a 5-point Likert-type scale where 1 = hardly ever, 2 = occasionally, 3 = sometimes, 4 = pretty often, and 5 = always. Overall scores were calculated by taking the average of the four items, with higher scores indicating greater sibling rivalry. In the current study, the alpha coefficient was .77.

Interparental hostility

This construct was assessed using the interparental hostility scale developed by Simons, Simons, Lei, Hancock, and Fincham (2012). The six-item scale asked respondents to report how often during their childhood and adolescent years their parents engaged in various hostile behaviors (e.g., “Shouted or yelled at each other because they were mad”) when interacting with each other. Responses were 0 = almost never or never, 1 = once in a while, 2 = quite often, 3 = often, and 4 = almost always. The sum of the six items produced an overall score. A higher score indicated a higher level of hostile interparental behaviors. An earlier version of this scale has been shown to correlate with observational assessments of marital interaction (Simons et al., 2012). The scale’s internal reliability for the current sample was very good (α = .90).

Parental hostility

The hostility displayed by parents toward the respondent was assessed separately using items developed by Simons et al. (2012). Maternal hostility was measured using a four-item scale that asked respondents to report how often during their childhood and adolescent years their mother (a) shouted or yelled at them, (b) criticized their ideas, (c) called them bad names, and (d) insulted or swore at them. The same items were used to assess paternal hostility. Items were answered on a 5-point Likert-type scale, in which 0 = almost never or never, 1 = once in a while, 2 = often, 3 = quite often, and 4 = almost always. In the current study, overall scores were determined by taking the sum of the maternal and paternal hostility items, with higher scores indicating a higher level of parental hostility. An earlier version of this scale has been shown to have high validity and reliability. For instance, child reports correlated with parent reports and with observer ratings (Simons et al., 2012). Reliability analyses indicated an alpha of .75 for our sample.

Sibling bullying

Sibling bullying was assessed with a standard questionnaire, the Sibling Bullying Questionnaire (Wolke & Samara, 2004), which was adapted from the widely used Olweus Bullying Questionnaire (Olweus, 2007). The questionnaire comprises seven items. Respondents were first asked to report (a) how often they had been bullied at home by a sibling during their childhood and adolescence. They then reported the frequency of the six following types of sibling victimization: (b) being hit, kicked, pushed or shoved around, or threatened; (c) having things damaged or taken, including money; (d) being called nasty and hateful names; (e) being made fun of; (f) being ignored or left out of their sibling’s social group; and (g) being told lies, having rumors spread about them, or believing that others do not love them. Responses were as follows: 1 = never, 2 = only once or twice, 3 = two or three times a month, 4 = about once a week, and 5 = several times a week. Overall scores were calculated by taking the average of the seven items, with higher scores indicating higher frequency of sibling bullying. The alpha coefficient for the current study was .85.

Well-being

Sense of competence

Respondents reported their sense of competence, which included feelings of global mastery and efficacy to navigate challenges. This construct was measured by the Mastery Scale, a seven-item scale constructed by Pearlin, Menaghan, Lieberman, and Mullan (1981). Respondents were asked to evaluate how strongly they agree or disagree with a series of statements about themselves. The responses ranged from 1 = strongly disagree to 5 = strongly agree and consisted of items like: “There is really no way I can solve some of the problems I have” (reverse scored) and “What happens to me in the future mostly depends on me.” Overall scores were calculated by taking the average of the seven items, with higher scores indicating greater sense of competence. Results have shown that a sense of competence, as measured by this scale, can buffer the emotional impact of persistent problems (Seeman, 1991). The alpha reliability was .75 for the current sample.

Internalized problems

We measured internalized problems using the Anxiety and Depression subscales of the Psychiatric Symptom Index (Ilfeld, 1976). Each of the two scales contains seven items (e.g., “During the past week, how often did you feel nervous or shaky inside?” for anxiety; “During the past week, how often did you feel downhearted or blue?” for depression), which are scored using a 4-point Likert-type scale (0 = never and 3 = very often). Overall scores of internalized problems were determined by taking the sum of the 14 items, with higher scores reflecting more severe levels of internalized problems. In the current study, the instrument demonstrates high internal consistency (α = .88).

Self-esteem

The French version of the Rosenberg (1965) Self-Esteem Scale was used to measure respondents’ global feelings of self-worth or self-acceptance (Vallières & Vallerand, 1990). It contains 10 items (e.g., “I take a positive attitude toward myself”; “I am able to do things as well as most other people”). The questionnaire is scored using a 4-point response format (1 = strongly disagree, 2 = disagree, 3 = agree, and 4 = strongly agree). The sum of the 10 items produced an overall score, with higher scores representing higher self-esteem. Its ease of administration, scoring, and brevity led Blascovich and Tomaka (1991) to recommend the use of this scale as a straightforward estimate of positive and negative feelings about the self. In fact, it is the standard against which new measures are evaluated (e.g., Bazińska, 2015; Kazarian, 2009). Reliability analyses indicated an alpha of .87.

Satisfaction with life

The Satisfaction With Life Scale (Diener, Emmons, Larsen, & Griffin, 1985) comprises five items (e.g., “In most ways my life is close to my ideal”), which are scored using a 7-point Likert-type scale ranging from 1 = strongly disagree to 7 = strongly agree. The questionnaire is narrowly focused to assess global life satisfaction and does not tap related constructs such as positive affect or loneliness. Respondents were asked to indicate their level of agreement or disagreement with the five statements. Responses to these items were averaged to measure global life satisfaction. The higher the overall score on the questionnaire, the more satisfied was the participant. In the current study, the alpha coefficient was .82.

Results

For all questionnaires, missing values were replaced with the participant’s mean score when 80% of the items on the scale or subscale in question were answered (n = 15).

Prevalence of Sibling Bullying

Although not a primary focus of the current study, we first examined the prevalence of sibling aggression (see Table 1). When asked about sibling bullying in general, around 28% of our sample reported being bullied by their siblings during childhood and adolescence: 17% reported being bullied only once or twice, 4% reported being bullied 2 or 3 times a month, 5% reported being bullied about once a week, and 2% reported being bullied several times a week. Yet statistics related to the different types of aggression showed that 79% reported experiencing at least some acts of sibling bullying during their childhood and adolescence. Verbal bullying (i.e., being called names and being made fun of) was reported more frequently than physical bullying (i.e., being hit, kicked, pushed or shoved, and having things damaged or taken) and social bullying (i.e., being ignored or left out and being lied to or having rumors spread about them), with being made fun of by their sibling as the most commonly reported act of aggression (see Table 1 for percentages).

Table 1.

Description of Sibling Bullying.

Type of Bullying	Frequency of Bullying, n (%)
Type of Bullying	Never	Only Once or Twice	2 or 3 Times a Month	About Once a Week	Several Times a Week
Sibling bullying in general	156 (72.2)	37 (17.1)	8 (3.7)	11 (5.1)	4 (1.9)
Hit, kicked, pushed, or shoved	145 (67.1)	47 (21.8)	17 (7.9)	6 (2.8)	1 (0.5)
Things damaged or taken	144 (66.8)	58 (26.9)	9 (4.2)	2 (0.9)	3 (1.4)
Called names	123 (56.9)	56 (25.9)	17 (7.9)	17 (7.9)	3 (1.4)
Made fun of	74 (34.3)	89 (41.2)	28 (13.0)	14 (6.5)	11 (5.1)
Ignored or left out	148 (68.5)	50 (23.1)	10 (4.6)	5 (2.3)	3 (1.4)
Lied to or had rumors spread about them	185 (85.6)	24 (11.1)	2 (0.9)	3 (1.4)	2 (0.9)

Descriptive Statistics

Means, standard deviations, and Pearson bivariate correlations are presented in Table 2. On average, young adults reported having been occasionally treated unfairly by their parents in comparison with their siblings, as measured by sibling rivalry, and having witnessed interparental hostility once in a while. The mean frequency of parental hostility fell between “almost never” and “once in a while.” Inspection of Table 2 also reveals a low average report of acts of sibling aggression during childhood and adolescence, and moderately high scores on the well-being measures.

Table 2.

Correlations and Descriptive Statistics of Key Variables.

	M	SD	1	2	3	4	5	6	7
Family dynamics: IVs
1. Parental hostility	4.09	3.59
2. Interparental hostility	5.22	4.97	.56***
3. Sibling rivalry	1.77	0.78	.38***	.21***
Mediator
4. Sibling bullying	1.55	0.63	.24***	.29***	.25***
Well-being: DVs
5. Sense of competence	3.81	0.66	−.32***	−.30***	−.30***	−.29***
6. Internalized problems	10.83	7.85	.30***	.29***	.15**	.21***	−.44***
7. Self-esteem	31.44	5.48	−.30***	−.24***	−.36***	−.29***	.51***	−.60***
8. Life satisfaction	5.20	1.06	−.35***	−.29***	−.24***	−.26***	.53***	−.50***	.60***

Note. IV = independent variable; DV = dependent variable.

p < .01. ***p < .001.

As shown in Table 2, all correlations between key variables were significant. More precisely, negative family dynamics during childhood and adolescence were positively correlated with sibling bullying. The more participants perceived issues of sibling rivalry and were exposed to parental and interparental hostility, the more they reported being victims of sibling bullying. Negative family dynamics and sibling bullying were also positively correlated with internalized problems, and negatively correlated with sense of competence, self-esteem, and life satisfaction. Correlations between predicted variables in the model and some demographic data (e.g., age, gender, number of siblings, birth order in the family, and nationality) were also analyzed (not shown in Table 2) to empirically select the appropriate covariates (Hair, Anderson, Tatham, & Black, 1998; Tabachnick & Fidell, 2013). These correlations revealed that gender was significantly associated with internalized problems (r = −.18, p < .05), such that women reported more internalized problems than men. Number of siblings (r = .15, p < .05) was positively associated with self-esteem, while birth order was marginally associated with sibling bullying (r = .13, p < .06). Considering these relations, gender, number of siblings, and birth order were entered as covariates for the associated predicted variables in our model.

Structural Equation Analyses

Path analysis models were tested in the EQS 6.2 program using the maximum-likelihood robust estimation method, a technique recommended by Hu and Bentler (1999) for samples of 250 participants or less. The overall model fit was evaluated using local fit estimators and goodness-of-fit indices (Kline, 2016). Acceptable fit is indicated by a relative Satorra–Bentler (S-B) χ² value (χ² / df) inferior or equal to 2.0 or 3.0, a value superior to .90 on the goodness of fit index (GFI) and the robust comparative fit index (CFI), a standardized root mean square residual (SRMR) smaller than .08, and a robust root mean square error of approximation (RMSEA) smaller than .07 (Hooper, Coughlan, & Mullen, 2008).

The proposed mediational model linking negative family dynamics during childhood and adolescence to measures of current well-being through sibling bullying was first tested. All paths were significant, with the exception of the path between parental hostility and sibling bullying (see Figure 1). As revealed by the global fit indices presented in Table 3, the proposed model did not reach acceptability. Results of the Wald test led us to drop the nonsignificant path between parental hostility and sibling bullying. However, removing parental hostility from the model did not lead to a significant improvement in fit (relative S-B χ² = 2.38, GFI = .94, robust CFI = .88, SRMR = .09, robust RMSEA = .08). Because the standardized residual matrix of the proposed mediational model indicated strong theoretically plausible relations between parental hostility and all measures of well-being (Polcari, Rabi, Bolger, & Teicher, 2014), parental hostility was added as a covariate for the four dependent variables in our final model. Adding parental hostility as a covariate has the advantage of removing predictable variance from the dependent variables’ error terms (Tabachnick & Fidell, 2013). The final model presented in Figure 2 provided a good fit for the data (see Table 3). All paths were significant and all goodness-of-fit indices indicated acceptability.

Figure 1.

The original mediational path model.

Table 3.

Fit Indices for All Tested Models.

Model	RelativeS-B χ²	GFI	Robust CFI	SRMR	Robust RMSEA[90% CI]
1. Original path model	2.49	.93	.88	.10	.08[.06, .11]
2. Final path model	1.93	.95	.93	.05	.07[.04, .09]

Note. S-B χ² = Satorra–Bentler χ²; GFI = goodness of fit index; CFI = comparative fit index; SRMR = standardized root mean square residual; RMSEA = root mean square error of approximation; CI = confidence interval.

Figure 2.

The final path model with parental hostility entered as a covariate.

A Satorra–Bentler scaled χ² difference test was used to compare the proposed model and the final model (Satorra & Bentler, 2010). The test showed that the final model was significantly superior to the proposed model, ΔS-B χ²(3) = 43.66, p < .05, and was therefore retained. This model accounted for 14.5% of variance in sibling bullying, 14.7% of variance in sense of competence, 14% of variance in internalized problems, 15.5% of variance in satisfaction with life, and 16.7% of variance in self-esteem.

The results suggest that interparental hostility and sibling rivalry during childhood and adolescence predict experiences of sibling bullying, which in turn predict young adults’ well-being. Moreover, all covariates reached the threshold of significance in the final model. Women reported more internalized problems than men and later born children reported more experiences of sibling victimization than earlier born children. Number of siblings was positively associated with self-esteem. Finally, parental hostility was associated with higher internalized problems, and lower sense of competence, life satisfaction, and self-esteem.

Discussion

The aim of the current study was to examine a theoretical model of risk factors and outcomes of sibling bullying victimization. The hypothesized model, in which sibling bullying served as a mediator, postulated indirect effects between negative family dynamics during childhood and adolescence, and young adults’ well-being. More precisely, we expected that negative family dynamics would be associated with more experiences of sibling bullying, which in turn would be negatively associated with young adults’ well-being. Statistical analyses revealed that the original model could be improved by dropping the path between parental hostility and sibling bullying. Yet the fit did not reach acceptability by removing parental hostility from the model. In the final model, parental hostility was treated as a covariate given its association with adolescents’ psychological outcomes (Polcari et al., 2014). The final path model provided an acceptable fit for the data. Partially confirming our hypothesis, our results suggest that the relationship between family dynamics and young adults’ well-being is, in part, mediated by experiences of sibling bullying. The indirect pathways linking family dynamics to measures of well-being are further discussed below.

Researchers previously stated that parents’ behaviors were the most consistent family factor affecting experiences of sibling bullying (Wolke et al., 2015). Our results add support to the few studies that have shown that family dynamics are linked to sibling bullying during childhood and adolescence (Bowes et al., 2014; Hoffman et al., 2005; Tucker et al., 2014). First, our results revealed that rivalry between siblings was associated with more experiences of sibling bullying. The positive relation between sibling rivalry and sibling bullying suggests that conflictual and aggressive interactions between siblings “might be motivated by inequality and a desire to improve one’s status” (Wolke et al., 2015, p. 922). Second, we observed that young adults who reported higher levels of conflict between their parents were more likely to be victims of sibling bullying. This finding is consistent with those of previous studies (Bowes et al., 2014; Tucker et al., 2014; Wolke et al., 2015). Moreover, the fact that the parental relationship is linked to the way children interacted with their siblings is in accordance with the social learning theory (Bandura, 1978). These findings are also in line with the family system theory (Cox & Paley, 1997, 2003; Minuchin, 1988), which postulates that individuals and subsystems in a family continuously influence one another.

The analysis of the relationship between sibling bullying and measures of well-being also converged with those of past studies (Bowes et al., 2014; Buist & Vermande, 2014; Duncan, 1999; Finkelhor et al., 2006; Mathis & Mueller, 2015; Tucker, Finkelhor, Turner, & Shattuck, 2013; Wiehe, 1997), showing that experiences of sibling bullying were associated with negative outcomes, even after controlling for demographic variables and parental hostility. More precisely, victims of sibling bullying reported lower sense of competence, lower self-esteem, lower life satisfaction, and higher internalized problems. These results are not surprising considering the central role of siblings in the lives of individuals across all stages of life (Dunn, 1983; Milevsky, 2011; Van Volkom, 2006; Whiteman et al., 2011). Given these results, it goes without saying that sibling bullying needs to be taken more seriously by parents and the general public.

Taken together, our findings support, albeit only partially, our hypothesis on the mediating role of sibling bullying in the relationship between negative family dynamics and young adults’ well-being. In terms of the observed mediating effects, we found that exposure to interparental conflict and sibling rivalry are linked to more experiences of sibling bullying, which in turn are associated with lower sense of competence, self-esteem, and satisfaction with life, as well as more internalized problems.

Although we predicted that all three family dynamic measures would influence young adults’ well-being through experiences of sibling bullying, our analysis suggest that this was not the case for parental hostility. More precisely, our results showed that the relationship between parental hostility and sibling bullying was nonsignificant. These findings appear to contradict those of Tippett and Wolke (2015) and Tucker and colleagues (2014), which showed that harsh parenting (e.g., shouting, quarreling, and spanking) increased experiences of sibling bullying. However, considering that the bivariate correlation between parental hostility and sibling bullying was significant in the current study, our results rather suggest that a large portion of the effect of parental hostility on sibling bullying was explained by the other measures of family dynamics. We also believe that this unexpected result could be explained by the types of victimization measured by the three family dynamics. Specifically, parental hostility is the only family dynamic measured in this study in which acts of parental aggression were aimed directly at the respondents. This could explain why the negative interactions between parents and their children, measured by parental hostility, was related to the victim’s well-being, without having to go through sibling bullying. Moreover, although parental hostility did not influence measures of well-being through sibling bullying, the results of this study suggested that parental hostility was an important covariate in the final model. More precisely, the strong relations between parental hostility and measures of well-being significantly increased the fit of the final model by removing predictable variance from the dependent variables’ error terms (Tabachnick & Fidell, 2013).

Although not directly tied to the primary goal of the current study, we also examined the prevalence of sibling bullying reported by young adults. We found that 17% of our sample reported one or two experiences of sibling bullying and 11% reported being frequently bullied by their siblings (at least 2 or 3 times a month). These results are somewhat low in comparison with the prevalence previously noted with similar samples (see Wolke et al., 2015, for a summary of previous work). Therefore, we cannot rule out the possibility that sibling bullying could have been underreported in the current study. If this was the case, it could have limited our ability to detect existent relationships between variables. Despite this possibility, there was adequate variability in the responses to items measuring sibling bullying and significant associations were found with other variables of interest. Furthermore, it is interesting to note that the frequency estimates of specific types of sibling aggressive behaviors (see Table 1) were higher than those obtained when asking a generic question about sibling bullying. These findings are in line with Hoetger and colleagues’ (2015) results, which indicated that a majority of college students did not consider sibling aggressive behaviors to be bullying.

Limitations and Future Directions

As with all studies, the present work has a number of limitations. First, our interpretations were limited by our inability to infer causal relationships. Although path analyses suggest directions of influence, all data were collected at the same time. Therefore, our results can only demonstrate the acceptability of the tested directional paths. Another limitation is that retrospective reports may have introduced accuracy bias given the amount of time passed since childhood. Experiences of sibling bullying may not have been reported or remembered accurately as a result of the evolution and the current quality of the participants’ relationship with their siblings. Participants may have answered the questions while thinking about their relationship in general, rather than focusing on the years in which sibling bullying was more frequent. A longitudinal study would likely improve the accuracy of our findings and allow clearer conclusions about causality. In addition, our study relied on young adults’ self-reports, which could inflate covariations among variables. However, direct behavior measures of interactions between family members are often limited to smaller samples (Gardner, 2000), which inhibits the use of more powerful statistical analyses, such as structural equation modeling. Our work focused on experiences of sibling victimization, yet siblings are frequently both victims and perpetrators. Future research could include both experiences of bullying to gain a better understanding of the associations between family dynamics, sibling bullying, and young adults’ well-being. Another limitation relates to the fact that we used data from young adults, mostly women, registered at a Canadian university, and the findings may not be generalizable to those from other social contexts. Furthermore, although we have provided support for the idea that family dynamics and experiences of sibling bullying provide information about one’s well-being, these are only a few of the important variables. Therefore, a large proportion of the variance of sibling bullying and of well-being was left unexplained in our final model. Young adults’ well-being is also the result of events and circumstances not included in the model under study, such as parental divorce (Amato, 2001) or peer victimization (McDougall & Vaillancourt, 2015).

Future research should investigate whether additional factors could contribute to the prediction of sibling bullying (such as, for instance, parenting intervention style and parental warmth). Documenting whether sibling bullying and parental hostility are associated with other measures of well-being or psychosocial functioning (such as perceived stress and quality of the current sibling relationship) or specific mental health disorders (such as posttraumatic stress disorder or adjustment disorders) is also of interest.

Implications

From a clinical point of view, our study supports the notion that therapeutic interventions and prevention techniques for parents should include education about the interdependence of family relationships and the link between family dynamics, sibling bullying, and young adults’ well-being. Knowledge about the salience of parental relations in promoting healthy relationships between siblings is also critical to the development of effective interventions in the sibling-bullying field, as parents are often unaware of their implication in the process of sibling bullying among their children (Pickering & Sanders, 2017). Parent management training programs can also serve as an opportunity to help parents support their children in developing effective conflict management strategies (Shadik, Perkins, & Kovacs, 2013).

Conclusion

Our work significantly adds to the literature by investigating the effect of the interplay of family dynamics and sibling bullying on young adults’ well-being. This study shows that disharmonious interactions between some family members can influence young adults’ well-being indirectly through sibling bullying. Clinicians and human service workers aiming to reduce bullying between siblings should advocate for a family-level approach by incorporating the underlying principles of the family system theory and the social learning theory into their clinical interventions. Further research in this area should be conducted to learn more about the risk factors and psychological outcomes of sibling bullying and to develop effective programs aimed at preventing and reducing this form of bullying.

Footnotes

Acknowledgements

The authors would like to thank Jolène Doucet, Karine Perron, Karine Roy, and Jannie Thibodeau for their assistance in running participants and in data entry.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Author Biographies

Andréanne Plamondon, MA, is a doctoral student at the Université de Moncton. Her research interest focuses on family and romantic relationships.

Geneviève Bouchard, PhD, is a full professor of psychology at the Université de Moncton. Her research focuses mainly on family psychology, couple psychology, psychopathology, and well-being.

Mylène Lachance-Grzela, PhD, is an assistant professor in the School of Psychology at the Université de Moncton. Her interests involve interpersonal relationships, parenting, and psychological well-being.

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