Brenda,

To put it simply (and there are some other variables to what I’ve written below),  BUT generally  people with late-onset CAH may carry:

1). Two mild mutations  =  MILD/MILD,

OR  2). A mild and a severe mutation =  MILD / SEVERE (SV)

OR 3). A mild and a null mutation= MILD/NULL (SW)

Therefore a parent with either of these three combinations will have late-onset CAH.

In the scenario that you mention; this late-onset person who fits into eg. the third group with the MILD/NULL combination, may marry or partner  a person who unknowingly has a NULL mutation and whammo the child may inherit the NULL component from both parents and YES the child will then be a salt waster (SW).

Now that technology allows, this is the reason why it is wise for anyone with CAH who is thinking of having a child to check out the apparently non-affected partner, as they may in fact be heterozygous for (carry)  one CAH mutation.

Rosalie