Can you give us a little more info?  Such as age of the child, boy or girl, and whether the child is a salt-loser or not? 

Three quick things which I think are critical:

1- Make sure the child has a medical identification bracelet.  My son's says: "Adrenal Insufficiency - Needs stress dose steroids".

2-Make sure your client understands what medication the child is supposed to be getting and when it is supposed to be given.  Failure to give the medication on a strict schedule, or frequently missing doses can have severe long-term affects.

3-Make sure your client understands what to do if the child becomes ill or suffers an injury.  This is something that should be discussed at length with the child's endocrinologist and specific instructions should be written down as it can be hard to remember what to do when faced with the stress of a child's illness.  Vomiting/diarrheal illnesses and high fevers can be fatal for children with CAH and should never be treated lightly.  Your client should have injectible hydrocortisone and know when and how to use it if needed.

There are lots of good sites on the internet.  I have a list of my favorites if you want to e-mail me.  I'd put them on here but I have to run....

I'm sure you will get lots of great responses.