I had a lab and a Maltese for years. The Maltese would go over and lay right next to my lab up against her belly. They even played a lot and the maltese kept my lab young. The funny thing was the Maltese could get the lab to fall down on her back! If you know how to be a good pack leader then both dogs will be fine. Also my mom's dog which is a Silky Terrier (yorkie/australian shepherd cross) they were best buds with my lab.