A matrifocal family consists of a mother and her children — generally her biological offspring, although nearly every society also practices adoption of children. This kind of family commonly develops where women have the resources to rear their children by themselves, or where men have more mobility than women. Some indigenous South American and Melanesian societies are matrifocal.

Among polygynous societies studied along the Orinoco river system in southern Venezuela, families are set up in two levels. The larger system consists of one man, one to five women, and their children. The smaller matrifocal family consists of each woman and her children. The children are reared by their mothers as they would in a simple matrifocal system, with most fathers not being closely involved.

A consanguineal family comes in various forms, but the most common subset consists of a mother and her children, and other people — usually the family of the mother. This kind of family commonly evolves where mothers do not have the resources to raise their children on their own, fathers are not often present, and especially where property changes ownership through inheritance. When men own important property, consanguineal families commonly consist of a husband and wife, their children, and other members of the husband's family.