Nonmarital childbearing increased dramatically in the united states during the latter half of the twentieth century, giving rise to families defined as unmarried couples with children. what is this family type called?

The most common terms for unmarried couples who have children together is "common law marriage" (or "common law wife," or "common law husband). A "common law marriage" is generally defined as a relationship between a legally unmarried couple who live together (and have for an extended period of time) and own or lease property together and, usually, have at least one child together.