Paper son

This may refer to a practice in which a relative or other person may be adopted as a son (or daughter, but usually a son) by someone who wants to have a descendant (usually male). I am familiar with a friend who is one of two daughters of a successful Chinese immigrant. The father wanted to have a son so a cousin from China was adopted as a son and entered the U.S. When the father died he shared as a son in the estate and later co-habited with a another cousin who had been brought here (female) who was not blood related.