A connection is said to be affinal when established via marriage rather than through the actual or mythological ties of descent. It is a kinship connection that results from marriage.
Affine is a person connected to ego by marriage in kinship relations. Consanguineal and affinal relationships are sometimes included when the term “kinship” is used, while other times, anthropologists reject these two classifications to highlight the differences between relationships formed via marriage and those created through consanguinity.
Since consanguineal and descent links were seen as the foundation of the social order, affinal relationships received comparatively little attention in kinship studies that were heavily influenced by lineage theory.
However, affinal ties that connect people or groups, as well as the affinal categories and linkages between them, are examined in greater detail according to alliance theory.
The reports of domestic violence and dowry harassment among individuals with affinal relations are the central areas of study in sociology. In addition, post-marriage adjustment with family members of in-laws is a significant concern in prosperous family life. The new cultural blending created after the union is significant in studying adaptation, assimilation, and acculturation.
The relationship between a father-in-law and son-in-law is affinal, whereas a father and son is a relationship of descent.
Unlike the mother-child direct link, which is of descent, the relationship between a mother-in-law and her spouse is affinal.