I'd say, keep Casper. I got Sprocket and Ivanova from a woman who said
she was suddenly allergic to ferrets after getting pregnant for the
second time. I guess I've gotta believe her.  The worst part of that
whole situation was that when I picked the ferrets up, the little girl of
the family was there and really upset that the ferrets were leaving.
I wasn't upset to be taking them however because:
 
a) when I picked them up they were in a SMALL rabbit cage, half the area
being taken up by the litter box, which had been used quite a bit,
showing that the fuzzies had been in there for a long time.
b) their nails were long, so long that Ivanova's back claws were tearing
from her toes
c) they had ear mites, showing more lack of care
 
The woman did give them, their larger cage, and some money for distemper
shots to me (enough for one ferret).  But I didn't give her my number or
address, and even if she had come for them the next day, I wouldn't have
let them return to her. They weren't being taken care of.
 
I have seen this from the other POV, and I *still* think Casper should
stay where he is now.  I agreed to foster a ferret for the Ottawa Ferret
Assoc., she was a darling little one called Mocha.  I kept her in my
bedroom, and after two days I was wheezing so badly I could hardly
breathe at night, and I regretfully had to give her up. Then I was told
that I was probably allergic to the cat litter. So, determined, I took in
Sprocket and Ivanova and have had absolutely no problems. They aren't in
my bedroom, and I switched to a dustfree cat litter.  But I still have no
right to find Mocha and demand to have her back, now that I know I have
no allergies to ferrets. I gave her up, and it's my loss.
 
[Posted in FML issue 1142]