Sundancer: The Saddle Creek Series by Shelley Peterson (Paperback)

"A troubled girl and a damaged horse find each other, and against all odds -- mistaken identity, abandonment, corruption, and fraud -- make an unbeatable team. His name is Sundancer, and from the moment he arrives at Saddle Creek Farm, Bird is fascinated by him. The horse is suspicious and guarded, touchy, and even cruel. Bird's Aunt Hannah calls him ""unrideable,"" and Bird has to admit that Sundancer might be trouble. But Bird, whose mother left her to be raised by her aunt halfway across the country, is a bit of trouble herself. How else would you describe a girl who hasn't spoken since she was six, and hears things no one else can hear -- like the thoughts of the animals she befriends? Sundancer is a wounded horse with a story he's not ready to share. Bird starts to feel like, maybe, they aren't so different, and maybe she needs him as much as he needs her. Will she be able to reach him before it's too late?"