Ella was the daughter of the emperor of the Levithian Empire, and the twin sister of Asher.
When the emperor was killed by his brother, Grath, Asher and Ella fled Levithia to Gallifrey to escape a similar fate. The twins found refuge in the woods of the planet, and made friends with the animals. When the twins came of age, the emperor's advisor, Rigel came for them and returned them home, where they took back their empire. (PROSE: The Twins in the Wood)