It was thought that Winter would learn to swim without a tail, but this forced her to swim with a "side to side" motion instead of the normal "up and down" motion. Winter's veterinarians feared that this unusual movement would damage her spine. Kevin Carroll, who had previously designed prosthetics for other animals (including dogs, an ostrich and a duck), volunteered to help after hearing about Winter on NPR and became Winter's prosthetist in 2005.