Wet nurse

A wet nurse is a woman who breast feeds and cares for another's child. Wet nurses are employed if the mother dies, or if she is unable or elects not to nurse the child herself. Wet-nursed children may be known as "milk-siblings", and in some cultures the families are linked by a special relationship of milk kinship. Mothers who nurse each other's babies are engaging in a reciprocal act known as cross-nursing or co-nursing. Wetnursing existed in cultures around the world until the invention of reliable formula milk in the 20th century.