Antecedents of sibling aggression and bullying victimization: The parallel and serial contributions of depressive symptoms and substance use.

Purpose: Sibling aggression has been recognized as a common form of family violence. However, further research is needed to elucidate several antecedents of sibling aggression perpetration and bullying victimization, such as substance use and depressive symptoms. Also, more studies are needed to identify the mediating pathways of depressive symptoms and substance use, which could explain the association between bullying victimization and sibling aggression perpetration as well as the association between sibling aggression victimization and bullying victimization, controlling for exposure to family violence and demographic variables. The current study tested two separate mediational models guided by the displaced aggression theory and self-medication hypothesis.

Method: The study used the Bullying, Sexual, and Dating Violence Trajectories From Early to Late Adolescence in the Midwestern United States, 2007-2013 dataset. The original sample consisted of 1162 middle school students who were initially surveyed and followed into three high schools. The first wave was used, which included a sample of 1101 adolescents. Structural equation modeling (SEM) was conducted to first examine whether bullying victimization was associated with sibling aggression perpetration. Then another model was conducted to test whether sibling aggression victimization was associated with bullying victimization.

Results: In the first model, results suggest that bullying victimization is positively associated with sibling aggression. Mediation results indicated depressive symptoms and substance use serially mediated the relationship between bullying victimization and sibling aggression. In the second model, results suggest that sibling aggression victimization is positively associated with bullying victimization. Parallel mediation results indicated that depressive symptoms alone explained the association between sibling aggression victimization and bullying victimization. Finally, serial mediation results indicated that depressive symptoms and substance use serially mediated the association between sibling aggression victimization and bullying victimization.

Limitations: Limitations include self-report measures and cross-sectional design; therefore, we could not make casual inferences.

Conclusion: The implications of these findings suggest the need for continued attention to school-based bully prevention efforts and family interventions. Such efforts could result in a significant reduction in bullying victimization and sibling aggression.