Family Structures in the United States

Nuclear

Description:

Named after the nucleus (the tightly connected core particles of an atom), the nuclear family consists of two parents and their biological offspring under 18 years of age. In middle childhood, about half of all children live in nuclear families.

nuclear family: family of four smiling and hugging each other

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Extended

Description:

If both parents are present and other relatives live with them (usually a grandparent, sometimes an aunt or uncle), that is an extended family. About 10 percent of school-age children live in such families.

Stepparent

Description:

Divorced fathers usually remarry; divorced mothers remarry about half the time. When children from a former relationship live with the new couple, it makes a stepparent family. If the stepparent family includes children born to two or more couples (such as children from the spouses’ previous marriages and/or children of the new couple), that is called a blended family.

Adoptive

Description:

Approximately 2 percent of children are adopted. Most adoptive families adopt only one or two children, in large part because so few children are actually available. As many as one-third of infertile couples end up adopting children.

Both grandparents, no parents

Description:

Grandparents take on parenting for some children when biological parents are absent (dead, incarcerated, sick, addicted, etc.).

Two same-sex parents

Description:

Some two-parent families are headed by a same-sex couple, with the biological child of one of them. [When same-sex couples adopt a child, that is listed as an adoptive family, above.]

Single mother—never married

Description:

In 2018, 40 percent of U.S. births were to unmarried women. By the time their children reach middle childhood, many of these women will have married or have additional help caring for their children.

single mother never married: single mother with her young son hugging her

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Single mother—divorced, separated, or widowed

Description:

Although many marriages end in divorce (almost half in the United States, fewer in other nations), many divorcing couples have no children. Others remarry. Thus, only 12 percent of school-age children currently live with single, formerly married mothers.

Single father

Description:

While most families in the United States with kids under 18 are headed by a mother (8.5 million), 2.6 million children were living with their single father in 2019.

Grandparent alone

Description:

Sometimes a single grandparent (usually the grandmother) becomes the sole caregiving adult for a child.