*Ystradwel verch Cadfan Gadeon
born about 0420 North Britain

father:
*Gadeon ap Cynon (Conan)
born about 0400

mother:
unknown

siblings:
*Gwrfawr Morfawr ap Cadfan Gadeon

spouse:
*Coel Hen "The Old" Dux Britannorum
born about 0420

children:
*St. Cenue ap Coel Hen born about 0450? Pennines, Britain
*Gwawl verch Coel Hen born about 0387? Pennines, Britain
Cynedda Wledig? died 0389
Garbaniawn ap Coel Hen

biographical and/or anecdotal:

notes or source:
ancestry.com
One source sites
*Gadeon ap Eudaf
born about 0322? North Britain
as the father. Looks difficult.