We heard the same as Liz - with proper treatment typically the kids reach 80-90% of their height. Personally I think it is very hard to tell how tall a person would be (without the CAH). Yes you can look at the parents height, but if I look back through our ancestors there are many variations. e.g. my 5'1" mom who had 5'5" and 5'10" parents e.g. my 5'10" husband and his 5'5" and 5'8" parents. I am now 5'5" but I didn't break 5' until 9th grade. I had a very late growth spurt. Who knows!