My Youngest Son Has Marfan He Is 19 And He

my youngest son has marfan he is 19 and he is having pain and tingling in his legs it presents when he is in bed with his legs bent at least that is how he discribes it at 19 he is getting close to 7 foot tall is he still growing? his older brother is just under 6 foot tall i am 5foot 10 inches it came from his mothers side