society > society and the community > kinship or relationship > [noun] > adoptive or foster relationship
adoptionc1384
milk-tie1870
milk kinship1885
1870 J. LubbockOrigin of Civilisation (ed. 2) iii. 66 The symbol of adoption represented not the birth, but the milk-tie.
1955 Jrnl. Royal Anthropol. Inst.85 60 Even a child might be married to the common wife by the milk-tie, and when he grew up claim conjugal rights in his much older wife.