Perceval’s mother in Perlesvaus.
When her husband, Alain, died from a combat wound, she became known as the Widowed Lady.
Perceval had left home as a youth, so her castle of Camelot was poorly defended when it was attacked by Cahot the Red and the Lord of the Fens. She sent her daughter, Dandrane, to find Perceval, who eventually returned and saved his mother’s land. Yglais and Dandrane lived out their days together.
Her brothers were Pelles, the Fisher King, and the King of the Castle Mortal.
Source
Perlesvaus | Early 13th century