Fairy Hill by Marita Conlon-McKenna (author)

Strange things are happening in Fairy Hill.

Thirteen-year-old Anna is upset when she is sent to stay with her dad and his new family at Fairy Hill in the west of Ireland. Hearing whispers in the wind, Anna senses she is being watched, but nobody believes her except the mysterious boy down by the lake. When her little half-brother, Jack, nearly gets lost, Anna suspects that someone is trying to steal him away. She wonders if the stories about the old house and the fairies are true. And if they are, could Jack be in real danger?