What was XXX's child's name?
Katherine Swynford
John Beaufort, 1st Earl of Somerset (1373--1410) Henry, Cardinal Beaufort (1375--1447) Thomas Beaufort, Duke of Exeter (1377--1426) Joan Beaufort, Countess of Westmorland (1379--1440) The descendants of Katherine Swynford and John of Gaunt are significant in English and Scottish history.
John Beaufort, 1st Earl of Somerset Thomas Beaufort, Duke of Exeter Joan Beaufort, Countess of Westmorland