Do you have more than one dog?

We have 2 dogs.we adopted one from our parents friend, he is a dauschund mix and was getting bullied by 2 other dogs. then a few years later we got a boxer puppy. even though the first dog is about 10 years old, he plays with our now 2 year old puppy and they lay together in the hallway. we were excited to get our puppy but wondered how he would get along with the other dog, but we introduced them in neutral territory (a park near our house) and they get along great!