Hi there. I cant' figure out why your other ferret didn't seem to react to noises until six months of age. I do know that kits can be very difficult to test sometimes if they have alpha like personalities. They just seem more head strong, more alert and therefore far more preoccupied (in other words they have extreme selective hearing). I really don't know of any other reason, unless your kit had any sort of infections going that were treated, or had severe ear mites that were treated that could have altered some hearing during the time period that you were testing your pet originally. It's so hard to say. More than likely, it the reason be that you are just far more skilled at home testing now. Home testing is tricky in that it takes planning, a lot of thought, much care with details and a whole lot of consistency. You said your second baby there was a panda. Most pandas are deaf (though some ferrets with panda markings were not actually born pandas, but born with some markings such as blazing markings ... and then fade to a panda by a couple months old). I think the fact that some are not born genetic pandas might explain why some pandas can hear? Possibly this ferrets personality made it easier to test, coupled with the fact that you are better at testing now. To see about testing, go to my site http://wolfysluv.jacksnet.com/deaf.html , and scroll down to push the button to read about testing. Also, push the button on the deaf pages that takes you to the deaf ferrets group. Many people share their experiences there, and there are archives of papers written about biting, and all sorts of things there. Wolfy [Posted in FML issue 4441]