Who is XXX's dad?
Constantine IV
Constantine IV (Greek: Κωνσταντῖνος Δ', Kōnstantinos IV, Latin: Flavius Constantinus Augustus) (c. 652 -- 14 September 685), sometimes incorrectly called Pogonatos, ``the Bearded'', out of confusion with his father, was Byzantine Emperor from 668 to 685.