Her maternal grandparents were Piers de Geneville, of Trim Castle and Ludlow, and Jeanne of Lusignan.
Agnes' father had just been created Earl of March, and was thus able to look for more powerful spouses for his children.
[1][2] Edward II and Queen Isabella attended the wedding at Hereford; dates of this event vary by historian, and it has been speculated that it took place in late May or early June 1328, or in 1329.
[3] Agnes and Laurence had one surviving son, John Hastings, 2nd Earl of Pembroke, who was born in August 1347.
[3] After Laurence's death, Agnes married John de Hakelut.