My son just started hitting me for no reason. Not out of anger or frustration, but just to, well, get a reaction I think. I really don't know why he does it. I don't know if I should ignore him, hit him back so he knows how it feels or put him in a time out. I can understand children hitting because they've been spanked or they've seen other children hitting, but this isn't the case. I don't know where he learned it from. Any advice?