Building kinship ties between two people who are not typically immediate biological kin is defined by

The answer is marriage. Building kinship ties between two people who are not typically immediate biological kin are defined by marriage. In addition, the idea of kinship groups based primarily on biological expectations and the nuclear family containing merely a mother, a father, and their children is a euro-american ideal. The kinship comprises biological descent and marriage associations but also put into practice such as nurturing and fictive kin.

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