parent-in-law

thumb|Emperor Pedro II of Brazil (seated) with his two sons-in-law, Princes [[Ludwig August of Saxe-Coburg and Gotha and Gaston of Orléans, during the Paraguayan War, 1865]] A parent-in-law is a person who has a legal affinity with another by being the parent of the other's spouse. Many cultures and legal systems impose duties and responsibilities on persons connected by this relationship. A person is a child-in-law to the parents of the spouse, who are in turn also the parents of those sibling-in-laws (if any) who are siblings of the spouse (as opposed to spouses of siblings). Together, the members of this family affinity group are called the in-laws.

==Fathers-in-law== A father-in-law is the father of a person's spouse. Two men who are fathers-in-law to each other's children may be called co-fathers-in-law, or, if there are grandchildren, co-grandfathers.