br Chilling Adventures of Sabrina” will will feature a flashback to Sabrina Spellman’s childhood on the Netflix series’ upcoming holiday episode.br Mckenna Grace will guest star as Li’l Sabrina on the show’s upcoming holiday episode, “Chilling Adventures of Sabrina: A Midwinter’s Tale.”br According to TheWrap, Grace was selected by Kiernan Shipka, the titular character, herself.br [Kiernan] texted me a picture of her with McKenna and said, ‘You have to get Mckenna.