Family
A family is, narrowly, parents and their offspring. More broadly, the group defined as those who have common ancestry. That is, the group produced as a result of sex leading to offspring. The term is also used more loosely to describe a group with some form of common characteristic or a group with a relationship (other than ancestral). In normal usage, however, family refers to the typical nuclear family.
A nuclear family consists of a mother, a father, and children. An extended family includes grandparents, aunts, uncles nephew, nieces and grandchildren. A single-parent family is one in which only one parent raises the children, often less effectively than in a nuclear family.
Children without families are known as orphans. They reside in orphanages, and they generally want to be adopted by loving parents.