A wet nurse's a woman who breast-feeds a baby that isn't her own. These children may be known as milk-siblings and in some cultures share a special relationship. When mothers nurse each other's babies, the act of wetnursing may also be called cross-nursing or co-nursing. Reasons for use A wet nurse may be employed if the mother of a baby's unable or unwilling to breast-feed her infant. The reasons may range from illnesses such as cancer and their treatment, to temporary difficulties nursing, to… (More on Wetnurse)