Bailey  (westie) is nearly 3 now and recently his nature has started to change. When out walking and we see dogs he normally he wants to play but now he growls at the usual dogs we see. My neighbour brought in her puppy to the house when it was 7 weeks put it to his face and he snapped. I know that she was wrong and told her its his territory and to let them meet outside since then he has been funny he has not changed with the kids he still loves people just dogs even any animal on the tv. Is this normal he was castrated at 1 1/2 with no probs.