Katie Price's Perfect Ponies: Pony in Disguise. Book 9

Jess, Mel, Sam, Amber and Cara are lucky enough to be able to spend as much time as they can with their favourite ponies at Vicki's Riding School. Grooming, sweeping the yard, even mucking out is fun when you love ponies as much as they do. Vicki's holding an Easter competition at the stables. But the event is so busy that nobody notices when the newest pony, Carol, goes missing until it's too late! The police aren't hopeful of finding her and Vicki's worried sick.
Sam and her friends are desperate to help find Carol, but what can they do?