Acculturation is typically defined in terms of individual responses to a dominant culture. In the present study, we examined the effects of different levels of acculturation among family members. Specifically, we looked at the health and risk behavior in Mexican-American children as related to a variety of psychosocial predictors, especially the differences in orientation toward Mexican- and Anglo-American cultures between them and their parents. Mother and child pairs (n = 106) noted their orientation toward both Anglo and Mexican cultures. Children's dietary and sedentary behaviors, tobacco and alcohol use (and susceptibility to use), and depressive symptoms were also measured. Males were more likely to be sedentary and consume higher levels of total fat and saturated fat, whereas girls reported higher levels of depression. Anglo-oriented youth consumed lower levels of calories from fat but also more alcohol than did their Mexican-oriented counterparts. The latter was particularly the case among those children who were relatively more Anglo oriented than were their parents. Parent-child acculturation differential in terms of the differences in Mexican orientation, in comparison, predicted susceptibility to tobacco use. However, the sum of the absolute values of these two differences predicted only lifetime alcohol use, and in a counter-intuitive direction. This familial measure of acculturation shows some promise, but additional formative research is needed to operationalize this construct.