Madog was still a child at the death of his father, Prince Gruffydd Fychan in 1289, so that the lands were placed in the custody of Queen Eleanor of Castile.
He was initially into the wardship of John de Warenne, 6th Earl of Surrey, and was the heir of the Lordship of Bromfield and Yale, and Castell Dinas Bran from his father, which would be taken from him during his youth by Edward Longshanks and be awarded to the Earl of Surrey, one of his relatives.
Madog ap Gruffydd asked the king for a suitable provision to be made for him, and seems to have been granted some of his father's lands.
The carving shows a shield with a lion rampant, surrounded by the inscription in the upper half of the slab.
[2] Custody of his lands was then granted to Edmund Hakluyt (Hakelute), who sold the wardship to Baron Roger Mortimer of Chirk Castle.