Mercury's injuries occurred when he was a mere 4 days old. He'd been accidentally hit with a weed whacker. Rather than put the kitten down, the veterinarian who tended to Mercury's injuries referred the kitten to human friends, who have experience working with bottle babies.
Though the severity of Mercury's injuries is a tragedy, there is a silver lining: Because of his young age, Mercury was able to adapt to his new body. His human friends nurtured the kitty as best they could, and now Mercury is thriving, despite his differences.