too many wrong assumptions. there are no good children. once you do something bad, that makes you a bad person. just like being a theif. you need to only steal once to be called a theif. a person needs to only lie once to become a liar. and since even babys can "lie" at times, that is they cry when they dont need food or to be changed, that makes them bad children too without them even knowing it. so based on this, santa still does exist at the north pole. the reason he is fat is because hs sits around all year and he has no presents to deliver considering there are no good chuldren in the world. i bet he was one of the 3 wise men who beared gifts at Jesus birth, the only perfect being in the world.
Note: i'm not serious, just wanted to show the whole "research" is based on unreliable guesses, let alone logical assumptions