We were visiting with some kids today and my 9 week old puppy was doing so great! He was having a blast and putting up with all their kid antics. I was supervising to make sure things didn't get too rough on either side. He got tired before they did and I think he needed a break, so he growled at one of them to back off. I told the kids he was done playing and took him away to give him some space. I was trying to respect his signals, but now I'm second guessing - should I have corrected him somehow? I don't want him to be afraid of kids or regularly growl at them in the future. But I do want him to give warning signals if he's thinking of biting. What should I do in the future if this happens again or if he starts growling regularly?