Shorty is very playful... though he can be mellow too - so he kind of alternates between being busy and being sleepy... As we get his scheduled more into my schedule of things, I'm sure we will see some evening out... Loves to play and knows had to play by himself too. He's doing great with my dog Sasha and learning the do's and don't of Sasha's rules with little fuss. He uses the doggie door too with no issues and will go out on his own but needs scheduled potty breaks so we can get him reliably housetrained. Does great in the crate too and sleeps in there at night without a peep. Quiet too when I get home so I'm able to greet my dog and get their dinner ready which is really nice.... He is a puppy, a little undisplined but very sweet and affectionate... We are working on sit with him and I'm sure the lightbulb is about to go on any second now, cause he loves getting treats!