Polybus

So the child lived in the palace, and became a son to Polybus and Merope, and heir to the kingdom.

To cheer him, the messenger now informs him that he is not the son of Merope and Polybus.

Polybus, the king, is dead, and Œdipus is proclaimed his successor.

Polybus being childless adopted the boy, who grew up believing that he was indeed the King's son.

The memories of Polybus and Merope come upon him, then the years of unnatural wedlock.