Hi A.,
My daughter failed her hearing test at the hospital and then passed it a few weeks later. There are a lot of things that impact pass/fail for the hearing test: the person giving the test, how quiet the room is, whether or not the baby is awake/asleep, if the baby still has junk in its ear from being born, etc. It kind of freaked me out when our daughter didn't pass the test. The pediatrician was very calm about it at the 3 day visit and said not to worry, a lot of babies fail the test for one reason or another. In our area, you can get a free evaluation from the school for the deaf (our pediatrician seemed much more inclined for us to take our daughter there rather than the people who evaluate the hearing at the hospital). Best of luck to your sister and her baby! And don't worry, either way, I'm sure her baby is wonderful!!
Cyndi