All children love horses! No wonder that one finds all kinds of musical pieces on this topic in the instructional literature for piano of the past centuries: pieces about big and little horses, seahorses and riders, and about motion in general, all rendered into music.
The resulting ideas on playing, nature and adventure offer a broad field of activity to all pianists who enjoy imaginative and varied music-making. And wherever the reference to "horses" is not immediately noticeable in the title, players can unbridle their fantasy and let it gallop!
Have fun!