I learned that lesson when my little 3 yr old GS got hold of mine. Took it away from him, no signs of injury, and then I looked again and he had blood all over his face and hair and two fingers were dripping blood. He did not cry until I put a pressure dressing on the fingers. A couple of hours later, at his daycare, he proudly showed off his bandages. It was hard telling my DS and DDIL what had happened. I now close my rotor between each cut.