This is not exactly related to "The Little White Horse", but I loved the book. Kea, a horse has to choose between being mates with her best friend and a horse she doesn't know well. A story with it's ups and downs, but it'll be interesting.

A young cat has potential as a warrior, but something else leads her along a different path. Follow this she-cat's story from kit-hood to adult-hood. Some warrior cat characters are included as well.