Has anyone here ridden a calf?

my daughter and i trained a calf for riding and we have it trained to steer to some homemade reigns and they go out on rides around the farm and around the fields and pastures and i think calfs would be the perfect mount for kids. But i havnt ever heard of people training calves just cows. So has anyone here trained a calf for riding. Here is a couple of pictures of her getting ready for a ride http://picasaweb.google.com/armface/U2#