A 7-month old that sleeps 12 hours at night!!  What a blessing!  I can understand your being hesitant to mess that up.

I believe that most endos recommend the 8 hour dosing because a dose of cortef only lasts 6-8 hours.  As you have probably seen on this board, there are a number of people who are doing circadium rythym dosing which I think requires 4 doses, one in the middle of the night.  The purpose of this is to try to mimic the way the a person without CAH would produce cortisol.  It seems like the people who are doing this are having very good results.

We have always done the 8 hour dosing (my son is now 6).  He usually gets his last dose around midnight.  I honestly can’t remember if we had to wake him up when he was a baby for this dose or if he swallowed it without waking up.  Now we stick the tablet in his mouth and he chews it up without waking.  It’s quite amazing.  But it would take a train to wake that kid up.  So far he has been maintained on a pretty low dose of hydrocortisone and his growth has been good.  So we are happy with this system.

That said, I am not aware of any research that shows that any of these dosing patterns results in better control or better growth.  So it seems to me that if your daughter is doing well, I wouldn’t worry about it too much.  On the other hand, your endo went to medical school and I didn’t, so you may want to take his advice over mine. :-)  Maybe you could try giving her a dose after she goes to sleep for a week or so and see how she does. 

Good luck!