Mabel de Beaumont
- Aft 1204(
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- 1 Mabel de Beaumont [1] d. Aft 1 May 1204
- 5th Earl of Devon William de Vernon Reviers d. Abt 8 Sep 1218
- 2 Mary de Vernon Reviers [1.1]
- Lord of Okehampton Robert Courtenay b. 1160 d. 26 Jul 1242
- 3 2nd Baron of Okehampton John Courtenay [1.1.1] b. 1218 d. 3 May 1274
- Isabel de Vere b. 1227 d. 11 Aug 1279
- 4 Hugh Courtenay [1.1.1.1] b. 25 Mar 1249 d. 28 Feb 1291
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- 4 Hugh Courtenay [1.1.1.1]
- 3 2nd Baron of Okehampton John Courtenay [1.1.1]
- 2 Mary de Vernon Reviers [1.1]