Hi Mari, I do have the same problem, my son is 25 months old he weighs 23lbs and is 31" tall. He still fits in 12month size clothes. When he was a year old he fit in 6 month clothes. It is something I have been concerned about for a long time. I bring it up to his endo and pediatrician all the time, they just don't seem to be as worried as I am, since his growth remains on the same curve (5%) and he is not dropping from that. However, my son is an eater, he eats more than his 7 year old brother. Which I guess is why I worry about the fact that he just doesen't grow. Does your son usually eat well? I use to worry about the kids not eating, but then I figured, they are not going to starve themselves, they will eat when they are hungry. But I would give him a multi vitamin like Polyvisol. Just so he is getting the vitamins he needs and make sure he is getting enough fluid. I hope this helps.