The most common way that family structures vary across cultures involves the role of the extended family. Modern industrialized and Western cultures favor the nuclear family over the extended family. Young married couples move away from their parents to start their own new family in a separate home. In many traditional cultures, the boundaries between the extended family and the nuclear family are much more diffuse. Multiple generations often live together in a single household and grandparents, uncles, and aunts play influential roles in the couple’s marriage and in the rearing of their children.