world to have older children in nuclear families to reach walking up to driving age ranges before meeting extended family members. Geographical isolation is common for middle-class families who move based on occupational opportunities while family branches "retain [their] basic independence". Some extended families hold family reunions or opportunities for gathering regularly, normally around holiday time frames, to reestablish and integrate a stronger family connection. This allows individual nuclear families to connect with extended family members. Australian Aborigines are another group for whom the concept of family extends well beyond the nuclear model. Aboriginal immediate families include aunts, uncles and a number of other relatives who would be considered "distant relations" in the context of the nuclear family. Aboriginal families have strict social rules regarding whom they can marry. Their family structure incorporates a shared responsibility for all tasks. Where families consist of multiple generations living together, the family is usually headed by the elders. More often than not, it consists of grandparents, their sons, and their sons' families in patriarchal and especially patrilineal societies. Extended families make discussions together and solve the problem. Indian subcontinent Historically, for generations South Asia had a prevailing tradition of the joint family system or undivided family. The joint family system is an extended family arrangement prevalent throughout the Indian subcontinent, particularly in India, consisting of many generations living in the same home, all bound by the common relationship. A patrilineal joint family consists of an older man and his wife, his sons and unmarried daughters, his sons’ wives and children. The family is headed by a patriarch, usually the oldest male, who makes decisions on economic and social matters on behalf of the entire family. The patriarch's wife generally exerts control over the household, minor religious practices and often wields considerable influence in domestic matters. Family income flows into a common pool, from which resources are drawn to meet the needs of all members, which are regulated by the heads of the family. Recent trend in the United States In the early stages of the twentieth century, it was not very common to find many families with extended kin in their household, which may have been due to the idea that the young people in these times typically waited to establish themselves and start a household before they married and filled a home. As life expectancy becomes older and programs such as Social