C.R.
if he's not in a preschool or regular playdate or mygym find one and join!! that'll help...also does he still nap?? If noy start up again...even if it's only downtime in his room for 45 minutes...it's just as good...he can look at books or play a leapster...listen to a soft cd...whatever, but you both need the break...3 and 4 are tough...they're too big to be little and too little to be big...chores help too..have him sort socks, put his clothes away, make his bed, clear/set the table...all my kids do this...they love to help when they're young and it's great for their self esteem! It won't be done the way you would do it...but don't fix it, just praise the effort and show them how..it'll come with time...and besides the less you do the more time you have to play with them!