Hi,
If you are talking of scant growth of hair, but you have had all other pubertal developments in order, do not worry, it will grow more dense in due course. It is also a family trait, so that it could also be affected accordingly. But however, if there is no hair at all, and / or , the other pubertal developments are not satisfactory, you should consult an endocrinologist and get treatment.
solace
You could always take insane wolf hormones stacked with other anabolic goodies. J/k... Ummm... that's a hereditary thing, and shaving every day can be a pain. Sure, it's fun when you're hungover and partied all night to look like a wild man and not shave, but it tears up your skin.
By doesn't grow, do you mean it grows in patches? My bestfriend who's a baller with the ladies has that problem, but he's Dutch and I forget what else. Can you grow sideburns? Or do you not even get a 5 o'clock shadow after a few days?