We currently have two very different cats. About 3 year old neutered male that has always been afraid of almost everything. He would go in the back yard of his own free will, but come running back in if a plane, helicopter, or even larger bird flew by. He enjoyed chasing squirrels, as long as they ran from him, after they started learning he would run, they started standing up and running him inside, but, insists that he must go outside each night after the sun goes down. We now have a about 13 week old kitten that has no fear of anything. He plays with our Husky mix dog, and purposely annoys the older cat by jumping on him, older cat bats him away and will run away from the kitten.