The basic kinship group in all societies.
Families vary enormously in structure and size.
For instance, the nuclear family usually consists of two adults and their children, biological or adopted. The extended family may include three or four generations, as well as uncles, aunts, and cousins. These may live and work together in common households, or exist simply as an extended kin network, linked by social relationships. In recent years, Western societies have seen an increase in the number of one-parent families, which may consist of an unmarried mother and her child or children, or a father or mother, left without a partner through death or divorce , and his or her children. The problem with one-parent families with small children is that it is often difficult for the parent to both care for the children, without the support of a partner, and to earn a living at the same time.