Who was the legal grandson of the Earl of Merica?
Ealdgyth, daughter of Earl Ælfgar Ealdgyth ("fl. c". 1057–1066), also Aldgyth or in modern English, Edith, was a daughter of Ælfgar, Earl of Mercia, the wife of Gruffudd ap Llywelyn (d. 1063), ruler of all Wales, and later the wife and queen consort of Harold Godwineson, king of England in 1066. She was described by William of Jumièges as a considerable beauty.
Humphrey, Duke of Gloucester Humphrey of Lancaster, 1st Duke of Gloucester, 1st Earl of Pembroke, KG (3 October 1390 – 23 February 1447) was an English nobleman. He was "son, brother and uncle of kings," being the fourth and youngest son of Henry IV and his first wife Mary de Bohun, the brother of Henry V, and the uncle of Henry VI.