My son "Adrian" is now 9 months I also have a 6 year old boy, well, shortly after the baby was diagnosed, they tested my older boy to make sure he didn't have the late onset CAH luckily he dosen't, But I do think it is a good idea to test other children that way you could be more aware, or have your fears put to rest. I hope this helps. For more information you might try contacting the Magic Foundation in Chicago. Anytime you need to talk, please don't hesitate to email. Kym P.