| b 1307, Of, Okehampton, Devonshire, England | Robert De Courtenay, [Sir Knight] | > | d 1334, , Moreton, Devonshire, England | John De Courtenay | Mary De Reviers | > |
| Hugh De Courtenay, [Sir Knight] | b 1218 | Hugh De Vere, [Earl of Oxford] | > | |
| | b 25 Mar 1248 | Isabel De Vere | Hawise De Quincy, Countess | > | |
| Hugh De Courtenay | d 28 Feb 1291 | b 1222 | Thomas Despencer | > |
| |b 14 Sep 1273 | | | Hugh Le Despencer | Mrs-Thomas Despencer | |
| |d 23 Dec 1340 | Eleanor Le Despencer | b 1197 | ||
| | | b 1240 | Mrs-Hugh Le Despencer | ||
| Robert De Courtenay | d 30 Sep 1328 | William Saint_John | ||
| |Elizabeth Mrs De Courtenay | Robert Saint_John | Godechild Paynell | | | John Saint_John | b 1199 | William Cantilupe | > |
| | | |b 1225 | Agnes Cantilupe | Milicent Gournai | > |
| Agnes Saint_John | d 29 Sep 1302 | b 1228 | ||
| b 1279 | | | Reginald Fitzpiers | ||
| d 11 Jun 1345 | Alice Fitzpiers | b 1208 | ||
| b 1234 | Alice | |||
| b 1212 | ||||