William de Ferrers, 5th Earl of Derby was born circa 1193 to William de Ferrers, 4th Earl of Derby (c1168-c1247) and Agnes de Kevelioch (c1174-1247) and died 28 March 1254 of unspecified causes. He married Sibyl Marshall (1209-bef1238) . He married Margaret de Quincy (c1218-bef1285) .
Children
| Name | Birth | Death | Joined with |
| Agnes de Ferrers (?-1290) | 1290 | William de Vesci (?-c1253) | |
| Isabel de Ferrers (-c1260) | |||
| Maud de Ferrers (-1298) | England | 12 March 1298 England | William de Vivonne (-1259) |
| Sibyl de Ferrers | |||
| Joan de Ferrers (-1267) | |||
| Agatha de Ferrers (-1306) | |||
| Eleanor de Ferrers (-1274) | 1274 | Roger de Quincy (c1195-1264) | |
| Name | Birth | Death | Joined with |
| Robert de Ferrers, 6th Earl of Derby (1239-1279) | 1239 | 1279 | Marie de Lusignan (-aft1266) Alianor de Bohun (c1240-1314) |
| William de Ferrers | |||
| Joan de Ferrers (?-1309) | 1248 Derbyshire, England | 19 March 1310 Berkeley Castle, Gloucestershire, England | Thomas de Berkeley (c1250-1321) |
| Agnes de Ferrers | |||
| Elizabeth de Ferrers (c1250-c1300) | 1250 England, United Kingdom | 1300 England, United Kingdom | William Marshall (-c1264) Dafydd ap Gruffydd (1238-1283) |
Footnotes (including sources)
| ‡ General |