Welcome to PT! I'm so sorry to hear of Blackjack's sister's trip to the Rainbow Bridge. Poor guy needs a break, huh? I've not had experience w/your situation but when I first got my calico, Puddy, she had a metal splint on her leg to try to straighten it out; she was born w/a birth defect and her leg stuck out like a wing and wouldn't touch the floor. The vet wrapped it too tight and the metal rubbed through the skin clear to the bone and caused a severe infection. So my vet removed the splint and let her go w/out one. (She walks w/a limp but it's better than the infection that she had.) So whatever you do, be sure that the splint is tight enough to stay on but loose enough that it doesn't cause problems. I love Maine Coons; I have two of them. My Specs is a handsome boy and my Pidge is a pretty girl. Looking forward to some pix of Blackjack and prayers going up that all will go well.....