I just read this thread now. I sort of agree with some of the things that were said in this thread so far. I am a physician so what I will be saying is probably some of the closest you will get to the truth. HGH will make any human being grow given the growth plates have not fused yet. What that means is that you need to go visit a pediatrician and ask about this issue and see if they are willing to xray your sons wrists and ankles. If the growth plates have fused the only thing HGH is going to do is make your boy grow heavier in weight and bulk up in muscle if he is exercising. Genetics play the majority of our predetermined height but not 100%. Environmentally a high protein diet promotes growth as well as long nights (by stimulating the pituitary gland to secrete HGH) such as in the arctics. The short of this is to go consult with a pediatric endocrinologist as they would be the right person to talk to. My humble 2 cents. I hope this is helpful.