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In page Isabel de Clare, 4th Countess of Pembroke:

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Isabel lived as a widow for only ten months after the death of William Marshal, though it was by no means an uneventful period. She wrote within days to the papal legate and the justiciar of England asking for the prompt delivery of her lands, and on 18 June 1219, the justiciar issued writs ordering local officers to hand over to her control of her inheritance in four English counties and in Ireland. Pembroke is not mentioned, which hints that her eldest son may have directly inherited the earldom as it may have been treated as a royal grant to his father, not as part of his mother's inheritance[citation needed]. The marcher lordship of Striguil also came to her.