Our little guy loves to kill mice. (Grosses me out
) We have lots of rabbits and so far he has not bothered their babies but I am sure if he had the chance he would. Like others have said it is just their natural instinct. We have a squirrel that lives in a tree in our front yard that has learned to taunt them. It will get within 3 feet of them and chatter at them till they chase it back up the tree lol. I love watching them outside.