The 1 year old dog we got 8 days ago isn't barking to sounds like our previous dogs did, he just barked for a couple of days when we first got him and had to leave the house for appointments, but he's okay with that now, we haven't heard a bark since? For instance, he doesn't react when I'm vacuuming, when the train goes by, when I sneak in the hall hoping my footsteps aren't heard like it did with my other dogs, when I make noise with the food container, he doesn't come running, doesn't seem bothered by thunder storms, yet his ears perk up when the door bell rings or when i call his name, but I just find it a bit odd that he doesn't bark to the sounds around him like the others did? We were told he is healthy. He seems to be happy and is adorable? Maybe it's just the breed or he was trained to be quiet? Guess it's a plus in a way, but he sure isn't any guard dog to alert when a stranger comes?