A Breach in Security

In the last few months we have put door knob covers on some of our doors to keep Savannah from getting in or out of a particular place. They have seemed to work pretty well, or so we thought. Jake watched Savannah last night while we went to the Jazz game, and when we got home he was telling us how Savannah pushed open the pantry door to get in, even though it has a door cover on it. In the 2 1/2 years that we've lived here, we've never know the pantry door to just "push" open. Well, he showed us exactly how to do it. Apparently Savannah had already figured out this little trick, so the door cover is useless.
Then there was this morning. Carter got up to go to the restroom and Savannah must have already been up, waiting for any sound of us. Right after Carter gets up I hear her start to say something and knock on her door. This is what she does when she's ready to get up and get out of her room. Not 20 seconds later does Carter come out of the bathroom and is on his way to get her, that he stops in our doorway and goes, "Oh my gosh!", which of course alerts me out of my somewhat aware sleep. Savannah had literally pulled apart (somehow) and taken the door cover off of the knob, opened the door and was holding it and said, "I break it!" What is the use of childproofing your house if the childproofing products don't work! I'm sort of hoping she just got lucky and didn't really figure out how to take them off or we might have a problem keeping her out of things and places. She's a smartie, that one.