The Island of Lost Horses by Stacy Gregg

Two girls divided by time, united by their love for some very special horses.

On a remote tropical island, twelve-year-old Beatriz stumbles across a wild mare with strange markings.
She can't believe that this horse is real, but soon a strong connection grows between them.

Then Beatriz begins to uncover an incredible history. Centuries ago, a young girl called Felipa and her horse, Cara Blanca, were running for their lives...

As the fates of Beatriz, Felipa and their mares become entwined, Beatriz learns that the future of the world's rarest horses - the Abaco Barb - depends on her.