John, King of England
Her paternal grandparents were Ralph Stafford, 1st Earl of Stafford and Margaret de Audley. Her maternal grandparents were Thomas de Beauchamp, 11th Earl of Warwick and Katherine Mortimer, a daughter of Roger Mortimer, 1st Earl of March. Through his paternal and maternal grandmothers, she was descended from Edward I and John, King of England respectively.