My son is 22lbs and in the 97% for height, so he's a big 10 month old. These pants fit him great, though they are a little long. The elestic is not too tight which I really like, I think he has a little room to grow. They are nice and thick, since he's crawling all over the place it's nice he has a little padding and these are roomy enough that he can get around. I will be buying more of these in other colors!