Ancient Egypt

GOD’S FATHER

Title used beginning in the Middle Kingdom for the father of a ruler who was not himself a king. During late Dynasty 18, it may have designated a king’s father-in-law, although the exact reason that it was used by future king Ay is unclear. It is not to be confused with the minor priestly title of god’s father used for priests of a certain god.
Historical Dictionary Of Ancient Egypt by Morris L. Bierbrier