We have a gorgeous 2 year old collie x who came to us as a rescue pup. He loves to play with other dogs and so we'd like to get a second dog this summer. While we would be happy, in theory, to have a rescue dog which isn't a puppy, our current dog is very submissive with other dogs and it would be nice if he could be top dog at home. For this reason we are thinking it may be better to find a puppy so there is more chance of this happening. Any thoughts / suggestions / advice?