Sam and Brimley are inseparable. Well, at least Sam won't separate from Brim. He follows the poor dog everywhere, trying to get him to play, cuddle or lick him.
Brimley puts up with it, occasionally enjoying a game of tug of war or chase, but mostly he just allows Sam to climb all over him. He's a good dog and mostly enjoys the attention.
Sam calls Brim his "brudder dog" (translation: brother dog) and when people ask him if he has any brothers or sisters he says "I have two brothers!" It's possible that when Sam was a baby, Sam believed himself to be dog. Since he barked at the door bell and all….
It's fun to see these two together, and I can see that Miles is following in his brothers dog loving ways. His biggest laugh to date? When Brimley licked his face. ;)