Gruffydd ap Madog Fychan was according to some sources the son of Madog Fychan

Madog Fychan

Madog Fychan may have had a claim to be a hereditary Prince of Powys Fadog 1304-c.1325. However his very existence is uncertain. It is claimed that he succeeded to his father Madog Crypl's titles on his death in 1304. However, it is more likely that Madog Crypl's son was Gruffydd, who was...

 the hereditary Prince of Powys Fadog

Powys Fadog

Powys Fadog or Lower Powys was the northern portion of the former princely realm of Powys which split in two following the death of Madog ap Maredudd of Powys in 1160...

 between 1304-c.1325.

Biography

It seems unlikely that Gruffydd ap Madog Fychan ever inherited the throne of Powys Fadog and he may have died before his father.

His son, Gruffydd Fychan II

Gruffydd Fychan II

Gruffudd Fychan II was Lord of Glyndyfrdwy and Lord of Cynllaith Owain c.1330-1369. As such, he had a claim to be hereditary prince of Powys Fadog.- Ancestry :...

 appears to have inherited the titles Lord of Glyndyfrdwy

Glyndyfrdwy

Glyndyfrdwy , or sometimes Glyn Dyfrdwy, is a village in the modern county of Denbighshire, Wales. It is situated on the A5 road half way between Corwen and Llangollen in the Dee Valley .-Owain Glyndwr:...

 and Cynllaith Owain directly from Madog Fychan

Madog Fychan

Madog Fychan may have had a claim to be a hereditary Prince of Powys Fadog 1304-c.1325. However his very existence is uncertain. It is claimed that he succeeded to his father Madog Crypl's titles on his death in 1304. However, it is more likely that Madog Crypl's son was Gruffydd, who was...

 sometime around 1325.