The Latin-language Chronicon Albeldense states that Ermesinda was daughter of Pelagius, the first king of Asturias, and his queen, Gaudiosa, and that her brother was Favila, the second king of Asturias.
He was assassinated in Peñalén, whence his nickname, by a conspiracy headed by his brother Ramón (el Fratricida, the Fratricide) and his sister Ermesinda.