Philippa Fisher: Philippa Fisher and the Stone Fairy's Promise: Book 3 by Liz Kessler
Philippa is looking forward to spending New Year in the village where her new friend Robyn lives. But her fairy godsister, Daisy - assigned to a new job but disobeying orders as usual - turns up to warn her that Something Really Bad (SRB) is going to happen! What they don't know is that a fairy has gone missing from the ancient stone circle on the moors - and that at ATC (Above The Clouds) Headquarters, the fairy godmothers in charge have a special plan for them. A perfect story for Liz Kessler's many fans, in which humans and fairies swap worlds with dramatic and unexpected consequences.