So there's Kal (you remember Kal, right?)
Me and my mom have temporary custody of my brothers 4 month old black labrador. His name is Rox (say hi, Rox!). Rox is a little spastic, but so very adorable. He and Kal already have an annoying little brother/put-upon big brother relationship. Rox bites on Kal's ears, cheek, legs, and Kal tries not to kill him. You know, like real siblings.
Kal is not an outside dog (something I can honestly say is all my mother's fault). He will run around outside for a little while, but then he wants to come inside. Rox is just spastic enough to want to be anywhere there is company. Outside, inside, under the toolshed, you name it. Now, when Kal wants to come inside, he will literally bang on the door with his paw. Sometimes he bangs so hard it shakes the house. There's a point to this story, just stay with me.
Kal, my little pumpkinhead, has figured out how to open the screendoor by pulling it with his paw. How do I know this? Because one day, when both dogs were supposed to be outside playing (and out of my hair), Rox was suddenly in the house. My mom asked me if I let the dogs inside. I gave her a very slow, "No?" Well, my mom went into the kitchen to find Kal pulling the door open, but he hasn't (not yet, anyway) figured out how to open it wide enough so that he can fit. But Rox is small enough to scamper right through the crack in the door.
Oh Kal. You are just too smart for this household.