Kin Groups and Descent. Traditional and modern Cahitan kin-group organization is based upon the nuclear family, the extended family, the household, the ceremonial kin group, and ceremonial-center membership. It has been suggested (Spicer 1969, 839) that the precontact social Organization was characterized by bilateral descent, bifurcate-collateral with Hawaiian cousin kinship terminology, local-group (ranchería) exogamy, supraranchería political organization only during periods of warfare, and a council of ranchería elders in peacetime. Spicer finds no evidence of precontact unilineal descent groups among the Yaqui.
Kinship Terminology. Although the traditional kinship terminology probably was bifurcate collateral with an emphases on the relative age of ones parents' and one's own siblings, today many families utilize a modified Mexican kinship terminology, lineal and Eskimo, with Cahitan terms applied to parents, siblings, and children and Spanish terms for aunts, uncles, cousins, and in-laws.
Ceremonial kinship is still extremely important, with godparents selected at times of birth, marriage, and ceremonial participation. Cahitan terms are used for godparents and godchildren. Groups of coparents become crucial cooperative units, especially in ceremonial contexts.