Through the Looking Back Glass Cedric's sister Cordelia moves into Enchancia Castle and the two siblings can't get along, so Sofia tries to help by taking a peek into their past. Details Casts Title Through the Looking Back Glass Genres Family Animation Kids Release Date 2017-08-18 Episode Runtime 00 Hours 23 Minutes Season Number 4 Episode Number 9 Production Companies Disney Television Animation, Disney Junior Ariel Winter Princess Sofia (voice) Travis Bryant Tyler (voice)