 This marriage, like those of his four brothers, did not produce any children; therefore when he died at Goodrich Castle on 24 November 1245, Margaret inherited a third of the Earldom of Pembroke as well as the properties and lordship of Kildare.Her dower third outweighed any of the individual holdings of the 13 different co-heirs of the five Marshal sisters which meant she would end up controlling more of the earldom of Pembroke and lordship of Leinster than any of the other co-heirs; this brought her into direct conflict with her own daughter, Maud, whose husband was by virtue of his mother Isabel Marshal one of the co-heirs of the Pembroke earldom.As a result of her quarrels with her daughter, Margaret preferred her grandson Henry de Lacy who would become the 3rd Earl of Lincoln on reaching majority (21) in 1272.