| William III de Ferrers 5th E. of Derby, E. of Chester (~1193 - 1253) |
Hugh XI le Brun Knt., Count of La Marche and etc. |
| Margaret de Quincy of Groby (~1218 - 1280) |
Yolande de Brain |
| Robert de Ferrers Knt., 6th Earl of Derby, etc. | Mary le Brun of le March |
| b. 1239, Of Derby, Lincolnshire, England d. bef 27 Apr 1279 bur. Priory of St. Thomas, Staffordshire, England occ. cen. im. . ud. |
b. abt 1242 d. aft 11 Jul 1266 bur. occ. cen. im. . ud. |
| Spouses: 1, 2 |