Though her father seems to despise the wild horses that roam near their Wyoming sheep ranch, twelve-year-old Tracy is determined to nurse one found in a coyote trap back to health
Tracy's father hates the wild mustangs, and his ranch hand is always leaving out traps for the coyotes. Tracy and her little brother Colin make it their mission to save the animals. One day they find a mustang colt caught in one of the wire coyote traps, and they work together to free him and take care of him until his leg is better. Of course, they have to keep it secret from their father. With the help of their friend Jason, Whitestar gets better, and Tracy starts dreaming that she could someday ride him.
It's been a long time since I read the Thoroughbred series, which I had loved at the time because those books felt like they were for older readers (until the later books, when the main characters became younger and younger and didn't age - in the original 20 books or so, the main character starts at age 13 and grows into an adult). This book, written long before Thoroughbred, is very definitely for middle grade readers. The plot is very simple and the conclusion pretty simplistic, though open-ended. It bothered me a little bit that Tracy didn't let Whitestar go as soon as he was healed and instead continued to try taming him. I'm sure as a young person I would have been annoyed that there wasn't more about riding - Tracy has never learned to ride because of her father's hatred for mustangs (and apparently all horses).