A family is a group of people who, in most cases, live together. They share their money and food and are supposed to take care of one another. Its members are either genetically related (like brother and sister) or legally bound to each other, for example by marriage. In many cultures, the members of a family have the same or a similar surname.
A family is said to be society´s smallest unit, its nucleus.
Types of families
Three types of family are: nuclear family, single-parent family and extended family.
- A nuclear family is made up of parents and one or more children living together.
- A single-parent family is one where there is one parent and one or more children.
- An extended family or joint families means father, mother, daughters, sons, grandparents, uncles, aunts, cousins, nieces and nephews. In many countries including China, Pakistan and India, extended or joint families traditionally live together.
Both the "nuclear family" and the "single-parent family" are also called the "immediate family".
Foster families are families where a child lives with and is cared for by people who are not his or her parents.
Some family members are genetically closer to each other. The following table gives examples:
|Inbred strain||not applicable||99%|
|Identical twins||not applicable||100%|
|Full sibling||first-degree||50% (2−2+2−2)|
|3/4 siblings or sibling-cousin||second-degree||37.5% (2−2+2⋅2−4)|
|Half-aunt, half-uncle||third-degree||12.5% (2⋅2−4)|
|Great grandparent||third-degree||12.5% (2−3)|
|First cousin||fourth-degree||12.5% (2⋅2−4)|
|Double first couisin||fourth-degree||25% (2−3+2−3)|
|Half-first cousin||fourth-degree||6.25% (2−4)|
|First cousin once removed||fifth-degree||6.25% (2⋅2−5)|
|Second cousin||sixth-degree||3.125% 3.13% (2−6+2−6)|
|Double second cousin||sixth-degree||6.25% (4⋅2−6)|
|Triple second cousin||sixth-degree||12.5% (8⋅2−6)|
|Quadruple second cousin||sixth-degree||9.38% (6⋅2−6)|
|Third cousin||seventh-degree||0.781% (2⋅2−8)|
|Fourth cousin||tenth-degree||0.20% (2⋅2−10)|
A group portrait of a mother, son and daughter on glass, Roman Empire, c. 250 AD
A family from Basankusu, Democratic Republic of the Congo.
Bjørnstjerne Bjørnson with grandchild, 1900
Queen Victoria, with her eldest daughter
Mennonite siblings, Montana 1937
Parents with child statue, Hrobákova street, Petržalka, Bratislava
The Family, a sculpture by Robert Thomas, in Cardiff
Family for Kids. Kiddle Encyclopedia.