My almost 3 year old is very small, he weighs 26lbs and is right around 36 inches, he is much smaller than his friends, but my family is very small. I am 5 feet 2 inches and my brothers are not much taller. My five year old is about 40 lbs and is about 44 inches. I take both kids to the Dr. next week so I will have more acurate numbers.