Margaret married Thomas Beaufort, Duke of Exeter before 15 Feb 1403. Thomas (son of John of Gaunt Plantagenet, 1st Duke of Lancaster, King of Castile and Leon. and Katherine Swynford de Roet) was born about 1377; died on 31 Dec 1426 in East Greenwich, Kent; was buried in Bury St Edmunds Abbey, Suffolk. [Group Sheet] [Family Chart]