My son was sweat tested when we got the prenatal diagnosis of CF on my daughter. We were told his sweat test was negative and would not need genetic testing. However, I decided to get him screened for THe mutations that Maggie has because I could not let it rest til I knew he did not have CF, every cold, stomach ache I felt worried about the whatifs. Our pediatrician did order the genetic test on my son; even though he didn't think it was necessary. It was for my own well-being. BTW, my son is not even a carrier.