Exposure to deviant friends has been found to be a powerful source of influence on children's and adolescents' aggressive behavior. However, the contribution of deviant friends may have been overestimated because of a possible non-accounted gene-environment correlation (rGE). In this study, we used a cross-lagged design to test whether friends'…

Differences in developmental trajectories of physical violence, vandalism, theft, and alcohol-drug use from ages 10 to 15 were studied. For females and for males, three trajectories of theft and of alcohol-drug use increased from 10 years to 15 years, while only the high trajectory of vandalism increased from ten to 14. All trajectories of…

This 17-year longitudinal study tested whether low peer-perceived acceptance and association with aggressive-disruptive friends during preadolescence predicted students' failure to graduate from secondary school. Participants were 997 Caucasian, French-speaking boys from low-socioeconomic status, urban neighborhoods. The boys were recruited in…