FAU: Does a ‘Bad’ Apple Spoil the Bunch?

Siblings bear responsibility for the spread of problem behaviors. Adolescents with a delinquent brother or sister are more likely to misuse alcohol and other substances than those without a delinquent sibling. Identifying the exact nature of that influence has proven difficult, because behavior problems in siblings can also be traced to friends, shared genetics and shared experiences with parents. Evidence describing how problem behaviors spread between siblings and across domains has been scarce – until now.