The Perfect Pony by Lois Szymanski

Today is the day Niki has been waiting for! She can get her own horse! As she takes her seat, she sees her dream horse, a glittering white horse with a silky mane. Just looking at her, Niki picks out the perfect name: Princess. After the supplies, the horses come out but none of them was the Princess. Suddenly, Niki sees a sad beaten up horse. "The Doggers will get him for sure," Niki heard someone say. Furious, Niki chose the black pony—just before Princess came into the ring! Just then, Billy Baily, her school's bully shows up and gets the Princess! After Billy teased her about her sickly horse, Niki goes home determined to prove to him how nice her horse could be.  After grooming him to perfection, Niki named her horse Blackberry. Suddenly she learns that Billy is having problems with the Princess, who he named Warrior. Could Niki possibly help?