Ruby's story.: The pony cubes collection

These are a series of book that follow on from each other. Ruby's story is the second book. Summer and Sarah are having their last riding lesson before Christmas. Polo keeps misbehaving and the lesson has to be cut short for safety. All Polo wants is to be in the bottom field with ruby the wild horse from next door. But is that all Polo wants? or is he trying to tell us something... Other books in the collection, Book 1, Summer and Polo. Book 2, Ruby's story. Book 3, The break-in. Book 4, T...