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In page Henry IV of England:

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Henry's relationship with his stepmother Katherine Swynford was amicable, but his relationship with the Beauforts varied. In his youth, he seems to have been close to all of them, but rivalries with Henry and Thomas Beaufort caused trouble after 1406. Ralph Neville, 4th Baron Neville, married Henry's half-sister Joan Beaufort. Neville remained one of his strongest supporters, and so did his eldest half-brother John Beaufort, even though Henry revoked Richard II's grant to John of a marquessate. Katherine Swynford's son from her first marriage, Thomas, was another loyal companion. Thomas Swynford was Constable of Pontefract Castle, where Richard II is said to have died.[citation needed]