One of Llywarch's successors in the court of Gwynedd was the poet Dafydd Benfras, who may possibly have been his son.
[1] He was a very nationalistic poet, and his fervent support for Llywelyn's policy of uniting Wales was a prominent element of his poetry.
In 1334, the survey of the Lordship of Denbigh recorded the gwely (in this case meaning tribal land) of Prydydd y Moch.
Also recorded is a "mill of Prydydd y Moch", and the poet may have had significant earnings from grinding the corn of local farmers.
It might refer to some defiant poetic lines threatening Gruffudd ap Cynan ab Owain Gwynedd, comparing singing to that prince with "casting pearls before swine" (Gospel of Matthew, chapter 7).