Margaret Holland ( 1385 - 30 Dec1429) was the daughter of Thomas Holland, 2nd Earl of Kent, who was the son of Joan "the Fair Maid of Kent," (wife of Edward the Black Prince and mother of Richard II of England) and grandson of Edward I of England. Margaret married John Beaufort, the son of John of Gaunt. They had six children, among them Joan Beaufort, wife of James I of Scotland, and John Beaufort , who became the grandfather of King Henry VII of England. After Beaufort died in 1410 (in the Tower of London), she married Thomas Plantagenet, Duke of Clarence , the son of King Henry IVKing of England, Lord of Ireland. Henry IV ( April 3, 1367 March 20, 1413) was born at Bolingbroke Castle in Lincolnshire, hence the other name by which he was known, Henry Bolingbroke . His father, John of Gaunt was the third surviving son of King Edward. They had no children. Margaret and both her husbands are buried together in a carved alabaster tomb in Canterbury CathedralCanterbury Cathedral is one of the oldest Christian structures in England. It is the Cathedral of the Archbishop of Canterbury, the Primate of All England and leader of the Church of England. As well as being as the mother church of East Kent it is also t that shows her lying between the two of them.