Please Help Me! Potty Problems

[Plastics017]

Hello, my son who will be 4 in four months seems to have developed a potty problem.  He is potty trained, he sleeps through the night without an accident, and doesnt have accidents at all during the day.  He potty trained fairly well, although he had trouble going poop on the toilet in the beginning and used to hold it and have accidents in his underwear, but that hasnt happened in a long time.  He is our middle child, he has an older brother of 6 and younger sister who is 1.  He is very sweet and listens for the most part, however the reason I am posting is because he seems to have developed a peculiar problem while going pee.  He wants us to be in there with him while he goes, and watch him pee, and he'll stand over the toilet forever squirming about.  He becomes EXTREMELY tempermental when he's in the bathroom.  For example, he went in there to go and called me in, I went in and watched him pee, then he was just standing there as always after he pees and I started to keep myself busy putting towels away, he became very upset almost instantly because I wasnt watching him, and I said "I'm watching, I'm watching!"  Thats how we have to act with him in the bathroom, its like walking on eggshells with him in there.  The other day he was extremely upset that his bubbles all went away, one time I flushed the toiled for him because he was taking too long and that threw him into an hour long temper tantrum, another time I didnt put the toilet paper in the toilet "correctly" and that threw him into another tantrum.  He seems to get set off immediately, and responds by throwing tantrums and throwing toys and hitting things.  I put him in his room and try to talk to him quietly, but it doesnt help, he wont talk to me about any of it.  I hate the negative attention that this behavior of his is generating from us, but I dont know what to do.  He even wakes us up in the morning when he gets up (about 6AM) and calls us into the bathroom to watch him pee.  Please, has anyone been through this before, and if you have, how did you resolve it peacefully?

[OB08]

Does he go to preschool?  Does he have a baby-sitter?  Does he express any interst in his father's bathroom activiteies?  

[Plastics017]

He doesnt go to preschool, my wife stays at home with the children during the day, and the only babysitter he's ever had has been his grandparents (my parents).  He sometimes expresses interest when I go to the bathroom, but not usually.  I figured I am going to just keep on being with him while he is going pee and hope that its just a phase!