Lily and the Prisoner of Magic

Georgie, Lily’s older sister, ended up under the power of spells from the terrifying, forbidden division of magic. Only her father can break the spell—he’s locked up in the Arcgate, a prison for wizards. But Lily and Georgie are just two girls, and they can’t save him on their own. They need help. And that means crossing the ocean and, in another country, finding the witch Rose. She’s one of the builders of the Arcgate and can free the girls’ father. But will the famous witch want to go back to the country where magic is banned?