Hello, I contacted Mr.Darrell Wolcott president of the Center for the Study of Ancient Wales about if Angharad was a late invention and he said that altough the first manuscript mentioning Angharad was from the fourtheen century, the sources of that manuscript given the people mentioned could be of as early as the first quarter of the 13th century. And more important, altough Angharad wasn´t mentioned in Harleian Ms 3859 written c. 970x985 neither was any son of Rhodri Mawr except Cadell, the son who was a paternal ancestor of Owain ap Hywel Dda and no one denies that Rhodri Mawr had other children.