In Egypt, "Pharaoh" was the title given to the deified kings. From earliest times in Egypt the pharaohs were worshiped as gods: the son of Ra, the son of Horus, the son of Amen, etc. depending upon what period of Egyptian history and what part of the country is being considered. It should be noted that prayers, sacrifices, etc. to the pharaohs were extremely rare, if they occurred at all - there seems to be little or no evidence to support an actual cult of the pharaoh.
The pharaoh was looked upon as being chosen by and favored by the gods his fathers. The pharaoh was never regarded as the son of any goddesses, but rather as the son of the Queen his mother, fathered by the god, incarnate as his earthly father. (A few seeming exceptions to this include a sculpture of Pharaoh Tutankhamen being embraced by his "parents" Amen and Mut, but the intent here seems to be to compare the king with their son Khonsu, rather than to actually claim that Mut was his mother.)

SEE ALSO Amon, Horus, Khonsu, Mut.