Mlynowski, Sarah. Whatever after #17

"Abby and Jonah might be moving away, which means it's time for one last mission through the magic mirror in their basement! And where does the mirror send them? Back into the story of Snow White, where their adventures all began. Snow White is happily ruling the kingdom, hanging out with the seven dwarfs, and getting ready for her big royal wedding to Prince Trevor (while the evil queen is safely locked away.) Abby's mission is clear: free Gabrielle, the fairy trapped in Snow White's mirror. But a few wicked fairies are up to their old tricks, doing all they can to stop Abby from succeeding... When Abby herself gets trapped, she must turn to old friends--like Cinderella, Rapunzel, the Snow Queen, Aladdin, and many more--for help, which leads to an epic fairy-tale showdown between good and evil. With a magical mix of courage, quick thinking, and fairy power, will Abby, Jonah, and all their friends be able to save the day?" -- Amazon