my partners 3 year old boy

[ruts30]

Does my three year old need to be evaulated or is this behavior age appropriate? He is very aggressive and seems to be out of control.  My partner and I are at a loss for how to help him.  He does not respond to punishments: timeout, spanking, loss of toys, privileges etc... He seems to be playing nicely 1 minute and then when our new 4 week old son comes down stairs he starts braking his toys, throwing around the room and getting moody and misbehavouring he screams from 10 mintues to an hour or more on Temper tantrums over nothing.  He screamed last night for almost an hour because he didn't want to go in to bed when its time. When he is in bed all he does is play about by getting out and jumping on/off the bed. We have tried everything from ignoring the temper tantrums to trying to head them off. He seems to lose complete control.
We hesitate to take him places because when it comes time to leave and he doesn't want to go, he has a Temper tantrums.  For the past several weeks, he has started hitting the family cat.  Unprovoked, In addition to all this, he ignores us when we ask him to do something he does not want to do. He acts as though he is deaf.   (We even had his hearing checked--all is ok.
There have been no major life events, the only thing i would say that has changed is the arrival of a new baby but we both from day 1 had him involved, he came to scans felt baby move around, we always show him attention by playing with him, both myself and my partner are very happy and there are no other family issues.  You also should know that he really can be loving child.  He is very cuddly and sweet--but only when he is getting his way.  Please help--we are afraid he is getting out off control and dont know what to do.

[margypops]

I forgot to add if he is not your child he would feel even more left out and his Dad should be paying him more attention whilst you look after the baby this is a double whammy for any child .

[margypops]

In my opinion it is appropiate in the fact that he is feeling jealous and usurped, he has a new sibling and he feels upset at the attention his new brother is getting whilst he gets punished, hitting a child never works it is merely showing him that its okay to hit others and is negative., .I suggest that you give him some one to one time that dad has baby whilst you play and take him out and make him feel wanted still..Walk in his shoes see how he must be feeling ..