Mervyn, Prince of Powys
- 904(
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- 1 Mervyn, Prince of Powys [1] d. 904
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- 2 Avendreg, of Powys [1.1]
- Idwal, Prince of N. Wales d. 942
- 3 Meyric, Of North Wales [1.1.1] d. 986
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- 4 Idwal, Prince of N. Wales II [1.1.1.1] d. 996
[ =>]
- 4 Idwal, Prince of N. Wales II [1.1.1.1]
- 3 Meyric, Of North Wales [1.1.1]
- 2 Tryffyn, of Powys [1.2]
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- 3 Isabel [1.2.1]
- Ivor Lord of Builth
- 4 Cynelin Lord of Builth [1.2.1.1]
[ =>]
- 4 Cynelin Lord of Builth [1.2.1.1]
- 3 Isabel [1.2.1]
- 2 Avendreg, of Powys [1.1]