DP and I found the bitties in the trash at age 3 weeks.  So, we were
their parents--the overflowing animal shelter couldn't handle them.
Suddenly the cat population of our 2 bedroom apartment doubled.

We kept the kittens in the bedroom.

Smokey was terrified of them (or of the mamacat he was sure was
somewhere around) and spend the first few days hiding.

Nocturne was pissed as hell.  It's the only time she wouldn't sleep on
our heads or even enter the room with the kittens.

It took a few days for Smoeky to go back to normal and a couple weeks
for Nocturne to stop snubbing us/eating plants out of spite/biting/etc.

So...give it time, purrs for a calm family, realize they're going to
need some time to get used to the idea.

--Fil

The kitten was outside, so the allergies might be from weeds or grass she
walked through.  A bath might help.Best wishes.   MLB

Karen, the situation you described is not unusual.  In fact, it is very
common.  You just need to give it more time and keep the cats separated for
awhile and give them time to adjust.  Above all, you cannot set a deadline
such as "this weekend" or "next week."  Cats do not work on a timetable, and
what works for one cat in a week may take three or four weeks for another --  
it just takes patience.  If you have read any of my messages about the time
when I adopted Duffy, then you know that I was fearful that Holly would
*never* accept another cat in the house.  We called her "the black tornado"
because she was so aggressive and quick to attack any other cat in my
vicinity.  However, they are now great friends.  I posted a "pictorial
history" of Duffy's introduction to Holly and also a later album that shows
the changes.  The albums can be seen at the links under my signature.  They
depict some of the steps I used in the introduction.

It is very important for you to separate the cats.  That is, Stranger needs
to be kept separate from Silver and Scout.  If your two resident cats are
agitated, they also need to be separate; but the time of separation for
those two would be very short.  By "separation," all I mean is in a room
with the door closed.  You could even use the bathroom for this purpose.  Do
*not* pick up one of the cats an "bring" it to the others for an
introduction.  That will only exascerbate the situation.  You need to let
the cats do this on their own timetable.  One of the most effective "tools"
is to work out an arrangement where the cats cat eat close together but not
actually come in contact.  If one of your doors has enough space under it to
slide a platter underneath, place some tuna on each end and slide it
half-way under the door where Stranger is.  Stranger will eat from that end,
and let one or both of your resident cats eat off the other end.

Thank you for taking this little one in.  I seem to recall that you were
even dubious about taking on two cats when you adopted Scout and Silver
(correct me if I am mistaken on this point), and look how well the things
have worked out.  I realize that your concern was for a different reason,
but the new set of problems is not insurmountable, just as the old ones
weren't.

Good luck with the 3 kitties -- and please don't give up.

MaryL

Photos of Duffy and Holly:     >'o'<
http://tinyurl.com/8y54 (Introducing Duffy to Holly)
http://tinyurl.com/8y56 (Duffy and Holly "settle in")

Good luck....and don't get discouraged. You should have seen Bosley
when he first came! He hated all the cats, and hated me too. Now he's
just big old love suck.
I always quarantined new strays for a while. I had a cat die from
feline leukemia once and am very suspect of new cats till they get
tested.  They can look so healthy and still infect your cats. It may be
a rare disease where you live; I believe it prevalent more in some
places than others. We see a lot of it here among strays.

Sherry