A girl inherits a miniature horse that develops an unlikely friendship with her half-sister's Jack Russell Terrier, which takes to riding on the horse's back.A girl inherits a miniature horse that develops an unlikely friendship with her half-sister's Jack Russell Terrier, which takes to riding on the horse's back.A girl inherits a miniature horse that develops an unlikely friendship with her half-sister's Jack Russell Terrier, which takes to riding on the horse's back.