My 4 year old always been kind of aggressive. Since she was 2 she had a Biting and hitting problem. The day care that she was attending was good about the issue. They would instruct her make a sorry card for the kids she used her hands on. Around three she started spitting and hitting again. So they made a sticker chart at her school. The chart had 4 categories (using gentle hands, playing nice, no spitting..etc). if she made threw the course of the day should would get to put Dora stickers on her chart. The behavior tailed off and it looked like she was growing out of it. So last year my wife got pregnant with my second child, everything was fine and my daughter was happy she was going to be a big sister. well about 4 months ago the behavior came back but it was worst this time. She was hitting kids unprovoked and biting and scratching teachers. To the point that they kicked her out the daycare, I can't blame them because there are other kids safety at risk. I've been documenting the behavior, I noticed that she really short tempered at home and spins out of control at the smallest hint of being corrected. she extremely hyper and has trouble listening or staying still to listen to directions. I've tried spanking her hand earlier but found that didn't work and it might show her that when I'm angry I use hitting instead of my words. I've tried time out, quiet time, sending her to her room and talking to her after she had a tantrum. She goes to her room and destroys everything, she incorrigible when this happens. So I made my home a positive environment, meaning I didn't allow my wife or her step sister to focuses on any negative behavior. we praised everything little thing she did. I made my wife spend more time with her because I figured she missed the bond with her mother. I've read countless books, I have "hands are not for hitting" and "words are not for hurting". all our interactions with my 4 year old are in reference to these books. She gets the concepts but she uses them to defended her bad behavior. If you tell her not to jump on the couch she'll say those are hurtful words. So today she hit a girl in a face with a truck at free play. I dont know what to do next? I feel like a bad parent and I know people are going to think the worst of us.