Is 120 a normal weight for a 12 year old?

Four-year-olds might be low or high in height or weight because of familial, constitutional, congenital, hormonal or nutritional reasons. Four-year-olds who have especially small or large parents will likely be similar to their parents in stature. Some children have a constitutional growth delay.

They start out average in size but have slower than normal growth during infancy and childhood. These 4-year-olds usually will have a growth spurt in adolescence and catch up to the average. Some small 4-year-olds might have congenital conditions such as Down's syndrome, a congenital infection such as herpes, or they might have been exposed prenatally to alcohol, toxins or smoke that inhibited their in utero and post-natal growth.

Hormonal or nutritional syndromes can also contribute to either small or big stature.