Katharine Newlin Burt (1882 - 1977) ran the Bar BC Ranch near Moose, Wyoming with her husband. She was a prolific author, writing romances, westerns, and the occasional children’s book. Several of her books were turned into films. Her husband, Maxwell Struthers Burt, was a novelist, poet, and short story writer, and, keeping it in the family, their son, Nathaniel, was also a writer.
Finding the book:reasonably easy to find, and not expensive.
Funk and Wagnalls Company, Inc, New York, 1965, 136 pp, illus Vic Donahue
Jenny Miller’s father is a wrangler on Mr Keene’s ranch. She likes a colt she calls Taffy, but Mr Mapes’ son, Stormy, is also fond of the horse he calls Smarty, and is devastated when he is sold. He secretly visits the colt, until he is found out, and then his father forbids him to trespass. The two children fight over who the colt should be with. Jenny is set to ride the colt in a race, but a family emergency prevents her from getting there, and Stormy gets to ride him instead. The result of the race helps to resolve the situation of who owns the horse.