My son is 11 and for the last year or so he has started lying and doing things behind my back that he has been told not to do. Stupid stuff but still deceptive. Like, I will say to him not to eat specific snacks that I have in the pantry because I'm trying to make things last, but when I'm not there he will eat it. Then afterwards when I ask him why he will lie and say he didn't. Blatant lie but still does it. He lies about all sorts of things, does things we've specifically said not to, and just says "sorry" when he gets caught but then does it again. He cries when I ground him or take away his phone and then I feel like the worst mom ever because maybe it's my fault for not being good enough. I've tried talking to him about it but it doesn't help. What the heck do I do? Is this normal for a kid his age? How do I get through to him? Am I too harsh?