Got a tom kitten now about 5 months of age. Noticed he has double set of cannines. Is he just growing his adult teeth or what? When do kittens start getting adult teeth. I am estimating his age. He was a small kitten about 8 weeks old I thought when I found him on side of road. Yes I stop and pick up abandoned kittens. But he could have been underfed. He certainly isnt little now an looks to be a big Tom when grown. Bigger than my other cat already but she is a small breed I think. I am having him neutered and vet said I had to wait til he was 6 months. So growing adult teeth might be a way of gettin a better idea of age. If thats what he is doing?