Who is the mother of XXX?
John VIII Palaiologos
John VIII Palaiologos or Palaeologus (Greek: Ίωάννης Η' Παλαιολόγος, Iōannēs Ē' Palaiologos; 18 December 1392 -- 31 October 1448), was the penultimate reigning Byzantine Emperor, ruling from 1425 to 1448.