Conduct disorder is a pattern of behavior in which individuals consistently disregard and violate the rights of others. The specific types of behaviors are varied and can include physical violence, repeated lying, damaging property, and stealing. Conduct disorder is believed to have roots in family interaction early in development, although its full expression may not occur until adolescence. For example, many studies show that family members train each other to engage in conflictive and coercive behavior that may lead to later conduct problems. This can be seen especially among siblings, as they can observe each other interacting with their parents and "practice" aggressive and bullying behavior with each other. During adolescence, however, individuals with conduct problems may form social networks with others, both friends and siblings, who are also trained in coercive behavior, and thus reinforce and encourage each other's antisocial tendencies.
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