We have 2 Boston Terriers, our oldest is 5 years and our youngest turns 1 in a week. As you can see, they are 2 peas in a pod, both are males. They are currently sleeping together on the couch and are the best of friends, no fighting, just nonstop running and chasing each other around the house (when not asleep). Mugsy (our oldest) was a little upset at first when we brought home the new pup, but after 2-3 weeks he started to realize that he was here to stay and accepted him "into the pack". My wife & I are 100% pleased we decided to get a second dog.