The name of this prince occurs in the Pedigrees as being father of Tywynwedd the mother of Tyvrydog mab Arwystli Gloff. Tyvrydog was a saint who flourished in the sixth century. In the Pedigrees, Tywynwedd is mentioned as the mother of Caradawc Vreichvras, of Gwyn ab Nudd, and Gwallawc ab Lleenawg.

Rolleston, however, alters the normal relationships within the genealogy, and makes Anlawdd the father of Yspaddadden, Custennin and Goleuddydd.

Eigr, the fair Ygraine of romance and mother of King Arthur, is likewise said to have been the daughter of Anlawdd, by Gwen, the daughter of Cunedda Wledig. This explains the relationship between Kilhwch and Arthur.