In human context, a family (from Latin: familia) is a group of people affiliated by consanguinity (by recognized birth), affinity (by marriage), or co-residence/shared consumption (see Nurture kinship). Members of the immediate family may include a spouse, parent, brother and sister, son and daughter. Members of the extended family may include grandparent, aunt, uncle, cousin, nephew and niece, or sibling-in-law. Close family members often share personal information with each other that they would not share with anyone else. A first-degree relative is one who shares 50% of your DNA, such as a full sibling, parent or progeny.
In most societies it is the principal institution for the socialization of children. As a unit of socialization the family is the object of analysis for anthropologists and sociologists of the family. Sexual relations among the members are regulated by rules concerning incest such as the incest taboo.
As the basic unit for raising children, Anthropologists most generally classify family organization as matrifocal (a mother and her children); conjugal (a husband, his wife, and children; also called nuclear family); avuncular (a brother, his sister, and her children); or extended family in which parents and children co-reside with other members of one parent's family.