Three Bull-Chieftains of the Island of Britain:
- Elinwy son of Cadegr,
- and Cynhafal son of Argad,
- and Afaon son of Taliesin.
The three of them were sons of bards.
The final note is from the White Book of Rhydderch.
Also, Afaon/Adaeon/Addon (various spellings exist) is also mentioned in other triads, and in the Dream of Rhonabwy in The Mabinogion as an "unfortunate murder." He is traditionally the son of Taliesin, but I have no record of his mother. He also shows up in The Black Cauldron in the same role, also killed midway through.