| Father | Sir Henry de PERCY 2nd Earl of Northumberland, Constable of England (1391 - 1455) |
| Mother | Eleanor NEVILLE Countess of Northumberland (1398 - 1472) |
| Sibling | Lady Katherine PERCY (1423 - 1472) |
| Sibling | Lady Eleanor PERCY (1415 - 1452) |
| Sibling | John PERCY (1418 - 1421) |
| Sibling | Sir Henry PERCY Earl Of Northumberland (1421 - 1461) |
| Sibling | Sir Thomas PERCY 1st Baron Egremont (1422 - 1460) |
| Sibling | George PERCY (1424 - 1474) |
| Sibling | Sir Ralph PERCY (1425 - 1464) |
| Sibling | Sir Richard PERCY (1427 - 1464) |
| Sibling | William PERCY (1428 - 1462) |
| Sibling | Anne PERCY (1444 - 1522) |