Ugh, sorry to hear!
Jackson has killed rabbits and one bird in the yard that couldn't fly well. It's their instinct but it's still hard as an animal lover. :\
He was at my dads house the other day and I looked out and was like "what is in his mouth?!" he was carrying a big rabbit he found under the deck WITH ITS HEAD OFF! Omg.. he was so proud too. I honestly don't think he could've ripped the whole head off that fast (it was likely already dead) but the fact that he found it and sniffed it out and was so happy. I saw him kill a rabbit once that he took by surprise and he shook its neck and it died instantly.