After her overprotective grandmother has a stroke, Maya, an orphan, leaves her extremely restricted life in California to stay with her mother's family on a remote Wyoming ranch, where she discovers a love of horses and encounters a wild mare that her mother once rode.
In this rhythmic cumulative tale Rosa Maria spends the week getting ready for her granddaughter's birthday party and trying to avoid attracting mice--unaware that the mice in her walls are preparing for a party of their own.
