The current longitudinal study examined the effect of the transmission of maladaptive parenting strategies from grandmothers to adolescent mothers on children’s subsequent development. Mexican-origin adolescent mothers (N = 204) participated in home interviews when the adolescent’s child (89 boys, 60 girls) was 2, 3, 4, and 5 years old. Grandmothers’ psychological control toward the adolescent mother was positively related to adolescents’ potential for abuse 1 year later, which was subsequently positively related to adolescents’ punitive discipline toward their young child. In addition, adolescent mothers’ punitive discipline subsequently predicted greater externalizing problems and less committed compliance among their children. Adolescent mothers’ potential for abuse and punitive discipline mediated the effects of grandmothers’ psychological control on children’s externalizing problems. Finally, adolescent mothers’ potential for abuse mediated the effect of grandmothers’ psychological control on adolescent mothers’ punitive discipline. Results highlight the salience of long-term intergenerational effects of maladaptive parenting on children’s behavior.