The Short-Term Influence of Sibling Proactive and Reactive Aggression on Subsequent Peer Aggression.

Although common, sibling aggression among youth is not well studied. This is a major omission in the literature, as sibling relationships have been found to influence other relationships. As such, the current study evaluates the links between self-reported sibling proactive and reactive aggression and peer proactive and reactive aggression six months later in a sample of 290 (54.8% male) elementary school-age youth who reported having at least one sibling. Gender differences in associations were also examined. Findings indicated that sibling reactive aggression was positively associated with peer reactive aggression six months later, over and above the stability of sibling proactive aggression and peer reactive aggression. Similarly, sibling proactive aggression was associated with peer proactive aggression over and above the stability of sibling reactive aggression and peer proactive aggression. However, gender differences were evident for proactive aggression. That is, sibling proactive aggression was associated with subsequent peer proactive aggression for boys only. Findings indicated that both sibling proactive and reactive aggression are associated with subsequent peer aggression within an academic year, suggesting the need to better understand sibling aggression for the prevention of aggression across relationships. Further, it appears that sibling proactive aggression is more influential on proactively aggressive behaviors toward peers for boys than girls.