Joan married Sir Thomas De HARCOURT, Jr, son of Sir Thomas De HARCOURT, Sr and Matilda GREY, on 2 May 1405. (Sir Thomas De HARCOURT, Jr was born in 1377 in Bosworth, Leicestershire, England, christened in Stanton Harcourt, Oxfordshire, England, died on 6 Jul 1420 and was buried in Stanton Harcourt, Oxfordshire, England.)