By Francis LaBelle, courtesy Thoroughbred Retirement Foundation Celestial City learned how to be a racehorse by continually proving himself against top competition. Each time he raced, he showed that the lessons he was learning were taking hold. Celestial City became a graded stakes winner, but just when his promising career was finally taking flight, he sustained an injury that ended his days as a racehorse. Now, he has a new home and a new purpose. On February 12, Celestial City joined the Thoroughbred Retirement Foundation's (TRF) herd at the Lowell...