Some accounts make him Amphitryon's nephew, with Heracles building Trachis for him. Muller supposes that the marriage of Ceyx and his connection with Heracles were the subjects of ancient poems.
According to some sources, he is portrayed as a relative of Amphitryon, with Heracles constructing Trachis for him. Muller proposes that the union of Ceyx and his relationship with Heracles was the focus of ancient verse.