The creole Chuvans' kinship system has never been fully described. Most of its unique features reflect the mix of the dominant Russian Orthodox tradition and the original Yukagir one. Kinship terminology, as revealed through isolated references, was generally of the Russian style, with strict terminological separation of consanguineal and affinal lines. Descent was usually patrilineal. As Chuvans received Russian-style family names (such as D'iachkov, Kobelev, Petushkov, Shitikov, Sobol'kov, etc.) through Orthodox conversion, children born of parents who were duly wed were registered under their fathers' names and tax-tribute statuses. Those born out of wedlock or in widowhood bore the names of their mothers (that is, the name of the mother's father). Major kin groups were formed by extended families, easily incorporating relatives from both sides and in-laws, because of the indigenous Yukagir tradition of matrilocal residence and of specific obligations of the son-in-law toward his wife's relatives.