Has your son had a bone age xray done? My son just turned 1 so I am still learning about all this - but, it seems from previous posts that the bone xrays are critcial for determining the bone age of the child. My understanding is that the xrays can give you additional info as to how quickly your child is growing. e.g. if his birth age is 3 1/2 but his bone age is 6 then it would appear he was being undertreated and may be growing too quickly. Also, does your son have an endocrinologist? If yes, what does he/she say?