Radish is a feisty pony -- and the best teacher Judy has ever had. He teaches her how to ride, how to go fast and far, and even how to fall off. But most of all, he teaches her to be patient. When Judy outgrows him, Radish teaches Nina all the same things, and most of all, how to be brave.

But girls grow, and ponies stay the same size. What will Radish do with no one to teach? It takes his running away for Judy and Nina to find the perfect solution, one that keeps Radish from being outgrown ever again!