[1] Humphrey Stafford was born on December 2, 1425, the elder twin brother of Henry.

His most prominent maternal aunt was Cecily Neville, wife of Richard Plantagenet, 3rd Duke of York and mother to among others Edward IV of England, Edmund, Earl of Rutland, George Plantagenet, 1st Duke of Clarence, Richard III of England, Anne, Duchess of Exeter, Elizabeth, Duchess of Suffolk, and Margaret, Duchess of Burgundy.

Lord Stafford fought under his father-in-law in support of the House of Lancaster during the First Battle of St Albans.

[1] Lady Margaret was a sister of Henry Beaufort, 3rd Duke of Somerset (executed 15 May 1464 after the Battle of Hexham) and Edmund Beaufort, 4th Duke of Somerset (executed 6 May 1471 after the Battle of Tewkesbury).

Her maternal grandparents were Richard de Beauchamp, 13th Earl of Warwick and his first wife Elizabeth Berkeley.