My little Luna -(tic) can't stand to leave a door alone. If it's open, she pushes it closed, if it's closed she tries to open it.
We've had to develop a habit of keeping all the room doors either closed or buy the little kick-stand type things to hold them open. Except the antique knob on my packaging room. (for my business. All my shipping materials are in there.) It has a little piece on the knob that you push down on to open it. It swings into the room from the hall.
Last night (we were playing a computer game) we heard a click. About 15 minutes later I noticed Luna wasn't laying in the hall at the door with her brother. I started looking for her. There she was in the "candle room".
This is her most fun game ever! Now we hear a click and "let Luna out of the candle room" she's opened the door, walked in, and shut the door locking herself in the room. She does it about ever 10 minutes All day long.

Then when she comes out it's like she hasn't seen us in years! OMG I'm SO happy to see my Daddy. Let me jump up on his lap. (She's 130 lbs)
Goofy dog
I love that doorknob but it might have to go.