Isabel (of Okehampton) Courtenay
- Yes, date unknownDrag or scroll to see more of the chart.
| Sir William Seymour | |
| D: | 1390 |
| Margaret Brockburn | |
| D: | Yes, date unknown |
| Cecilia Beauchamp | |
| B: | Abt 1321 |
| D: | 7 Jun 1394 |
| Roger Seymour | |
| D: | Between 1380 and 1390 |
| Margaret (of Basing) St John | |
| B: | Abt 1308 |
| D: | 19 Nov 1361 |
| John (2nd Lord of Hacche) De Beauchamp | |
| B: | Aft 4 Oct 1304 |
| D: | 19 May 1343 |
| Isabel St John | |
| B: | 29 Jun 1333 |
| D: | 16 Oct 1393 |
| Henry De Burghersh | |
| M: | Abt 1347 |
| D: | Yes, date unknown |
| Hugh (Yr of Basing) De Poynings | |
| D: | 26 Dec 1426 |
| Elizabeth Ferrers | |
| D: | Yes, date unknown |
| Eleanor Welles | |
| M: | Bef 1408 |
| D: | Yes, date unknown |
| Thomas (of Basing2nd Lord St. John) De Poynings | |
| D: | 7 Mar 1428-1429 |
| Joan Strange | |
| D: | Yes, date unknown |
| Luke (of Basing 1st Lord 'St. John) De Poynings | |
| M: | Bef 29 Jan 1349 |
| D: | Bef 4 Jul 1376 |
|
| Isabel (of Okehampton) Courtenay | |
| D: | Yes, date unknown |
| John (of Basing 1st Lord) De St John | |
| B: | Abt 1273 |
| M: | Bef 1308 |
| D: | Bef 4 Apr 1329 |