Konstantin married, but his spouse's name is unknown, and from this marriage Konstantin had a daughter, Jelena, who in 1392 married Byzantine Emperor Manuel II Palaiologos (r. 1391-1425). Manuel II and Jelena had several children, among whom were the last Byzantine Emperors John VIII (r. 1425-1448) and Constantine XI (r. 1449-1453). Constantine XI, the last Byzantine Emperor, who died defending Constantinople from the Ottomans in 1453, was known by his mother's surname, in Greek, Dragáses (Δραγάσης). Constantine XI was named after his grandfather.