A Stallion Called Midnight - Book
(A rewritten version of Midnight on Lundy) by Victoria Eveleigh.
Midnight is a wild stallion who won't let anyone tame him. Anyone, that is, except Jenny - but that's their secret. Jenny dreads the day she'll have to leave him on their island home and go away to school, especially as rumours are spreading that Midnight is dangerous. How can Jenny keep Midnight safe and free if she's not there to protect him?