Nothing wrong with smoking with a dog as long as the dog enjoys it, but I don't agree with smoking with a dog that young. When you do expose a dog to marijuana, you should wait until they're older, and do it very slowly (not continuously blowing smoke in the face) to gauge whether or not that particular dog enjoys it or not. Getting a tiny puppy stoned against it's will is just going to scare it. There's no way to tell at that age if its going to be a dog that likes it or not, and i can't imagine a puppy that young would enjoy it regardless. In fact, it's my understanding that very few dogs do, so no, definitely not cool to get a 8-12 week old puppy high.