That's nasty!!!!!!, I have a three year old and babysit and 4 year old and I pay close attention and stand at the door and when they walk out we go over the list, DID YOU WIPE, DID YOU FLUSH, DID YOU WASH YOUR HANDS WITH SOAP. I'm not sure about the sign, It may work for a little bit, but after a while it just becomes another forgotten about decoration. Just like all those signs on the gas pumps. It could be like the other lady said, he may just be mad at your husband if he hasn't been around that much in his life and trying to get back at him. It could be just a bad habit in which case train him like I've been taught to train my kids. Repetition. Make him go in there every time he forgets and go through the motions of wiping, flushing and washing his hands 10 times everytime he 'forgets'. Tell him if he's going to act like a kid, your going to treat him like a kid. After 2 days, if he still continues to 'forget' continue to make him go through the motions and clean the tolite every time. It shouldn't take to long before he doesn't want to 'forget' anymore.