| Father | Earl Richard De Clare Iv, of Gloucester (1222 - 1262) |
| Mother | Maud De Lacy Countess of Hertford And Gloucester (1223 - 1289) |
| Sibling | Gilbert De Clare 7th Earl of Gloucester (1243 - 1295) |
| Sibling | Isabel De Clare (1240 - 1271) |
| Sibling | Gilbert De Clare 7th Earl of Gloucester (1243 - 1295) |
| Sibling | Bewes Declare (1248 - 1294) |
| Sibling | Bevis Bozo Benet De Clare (1248 - 1294) |
| Sibling | Robert De Clare (1249 - 1262) |
| Sibling | Margaret Declare Of Gloucester (1249 - 1313) |
| Sibling | Sir Gilbert The Red IV De Clare Earl Gloucester And Hertford (1243 - 1298) |
| Sibling | Rohese De Clare (1252 - 1316) |
| Sibling | Rose Declare (1256 - 1272) |
| Sibling | Eglentina De Clare (1257 - 1257) |
| Sibling | Thomas De Clare of Thomond 1st Lord of Inchiquin And Youghal (1247 - 1287) |
| Sibling | Thomas De Clare Lord of Thomond (1245 - 1287) |
| Sibling | Maud De Clare (1252 - ) |