I have a 15-month-old son and nothing that I have tried for his behavior works. He hit's when he's mad and throws things, goes limp and throws himself on the floor. I have tried timeout, looking him in the eyes and saying no hitting. He’s very attached to me so I’ve even tried walking away to where he can’t see me anymore. If we don't let him get want he wants he stands there for a few seconds and then throws himself on the floor and throws a fit. Or just starts hitting you, If you tell him no or try to make him stop or try to hold him when he's mad he'll sling back and try and hit you with his hand or hit you with what ever he can. Also he throws his toys at my husband or me but he hits or throws things mainly at me. He laughs or smiles at me when I try to discipline him even though I'm stern with him. Sometimes he hits when playing and I reinforce no hitting then and sometimes it's because he's mad. I don't know what else to do to get this to stop or at least get better. It's been going on since he turned one. Any suggestions?