I have never heard of this happening.. We have a ferret - Jynx. We adopted her in December from a lady who decided she was not ferret person. We were told she was a female. Her papers from the petstore were never sent in but they said she was a female. I sent those in and now have Jynx's papers and health guarantee that Marshall has. When we got Jynxie she was a big ferret compared to our other females. At 3 months old she was bigger than our females. She was almost as big as our 2 and a half pound male. We just thought she is a BIG girl! She is now 5 months old and has to weigh about 3 pounds and she is still growing. Sheis by far our most aggressive ferret. We started calling her the alpha female. Whenever we would get a new ferret, Jynx would attack them even after all the bathing to get them all smelling the same. Even after I would put bitter apple around the new ferrets ears and neck. Even after I would put vanilla on her nose to lessen her sense of smell. We, sometimes, have to separate her from our other ferts because she plays so rough. I kept thinking this is weird, she is sooo- masculine compared to our 4 other females. I did notice that she had a nub on her tummy but when her papers said female, I thought female! A lady that runs a ferret shelter, looked at Jynx and thought like we did that it was a bulging ambilical nubin. Tonight I decided to compare ferret genitalia. I know "Fun evening!" hehe My husband and I both are convinced Jynx is a boy. I even pushed on the skin below the nub, and I do feel the bony line that our other boys have. The problem: Is Jynx neutered? I cannot see a scar in the normal spot, as I can on the other males. And since Marshall's thought he was a female.. He is not stinky. Aggressive? Yes. But more in a babyish way. Not a violent way, if that makes sense. Seems to me that the vets that do the spaying and neutering at Marshall's would know if it was male or female and do the surgery accordingly. If he is not neutered I do think that Marshall's should pay to have it done. Teresa 5 skinkids and 9 furkids [Posted in FML issue 4033]