It could be your punishments are part of the problem , It has been said by many experts that spanking especially a belt, actually has an adverse affect on children, have you thought he may be copying ,/acting out .He is unhappy perhaps time to focus on what is m,aking him unhappy , set firm bounderies, if he misbehaves take away something he cares about , a game , TV tell him he has to behave then he gets it back, are you consistant in the time outs. Have a seat in a room tell him he has to stay there when he comes off the chair you take him back, no yelling , no words,bequiet ..if he hears you yelling he will copy you. I also believe that distraction works if the day care person gets him interested in playing outside games and activities, reading, he is also missing you and his Dad when you are at home he needs you not day care.. Good luck, I realise its not easy trying to do it all..