Books with author Mary O'hara

"Thunderhead," a roving, big white stallion, causes problems for the Wyoming ranchers when he leads their blue-blooded racing mares off to join his wild horse herd in the mountains. Escaping gunfire, he runs off one night with a young rancher;s mare, a possible winner of the Governor's Stake trotting race. The mare is recaptured and entered in the race against the horse owned by the father of the young rancher's sweetheart, and this puts a damper on their romance.

As Ken becomes an adult, weathering the depression, rough ranch life and family conflict, Flicka - the mare from My Friend Flicka - gives birth to her colt during a thunderstorm. Ken's mother sees the thunderheads in the sky and his name becomes prophetic. He lives up to his name and the destiny of the colt is to be determined by the wild mountains that are his home. While the first book in the series was perhaps geared towards children, this is both grittier and deeper than Flicka. The strong female character is in conflict and is considered a role model in her effort to determine what she wants from her life and finding a solution.