Galfridus Yonge
M
| Father | Ierwerth, Welsh King |
| Mother | Margaret Yonge |
Galfridus was born. Galfridus married Margareta Petro in England. Galfridus and his brother, Morgan took on the surname of their mother.
Family | Margareta Petro |
| Child |
| Father | Ierwerth, Welsh King |
| Mother | Margaret Yonge |
Family | Margareta Petro |
| Child |