Isabel de Clare, 4th Countess of Pembroke Cambro-Norman-Irish noblewoman and one of the wealthiest heiresses in Wales and Ireland (1172–1220) Parents Aoife MacMurrough Richard de Clare, 2nd Earl of Pembroke Children Sibyl Marshal Eva Marshal Walter Marshal, 5th Earl of Pembroke Richard Marshal, 3rd Earl of Pembroke Anselm Marshal, 6th Earl of Pembroke Joan Marshal William Marshal, 2nd Earl of Pembroke Isabel Marshal Gilbert Marshal, 4th Earl of Pembroke Maud Marshal Siblings Gilbert Clare Alice de Clare Partners William Marshal, 1st Earl of Pembroke