This is typical with female cats.....They seldom get along, unless they are
kittens, or, at least one is a kitten. The problem is, they are very
territorial, and the one you got first is threatened by the newcomer. I have
five cats and three are females. I have found that it just takes time. The
newcomer will gradually learn how to fit in. Try to not let any one of them
exclusively occupy one section of the house.....Make them share the food and
sleeping quarters, by picking them up and carrying them there if necessary.
Let them know that they must share the house equally, and they will learn to
do so. They may even develop a kind of guarded friendship, but it will never
be as close as two males would establish.

Bill is right; female cats are always the most difficult to house together.
They are *so* territorial, perhaps because they naturally need to protect
their kittens from predators and also to safeguard that territory's food
supply.  On the other hand, social groups of female wild cats will cooperate
with each other over the nursing and guarding of their kittens.  Alas, you
have no kittens ... no, don't even go there! :~)

Because of these natural behaviours and my own experience (I have 2 female
cats), I am inclined to disagree with Bill over the territories in your
home.  My cats each have indoor territories that are entirely their own.
Because my Cheetah (like your Kali) is more reticent and nervous, I
vigorously defend her territory for her.  I'll do the same for Panther,
although it's not usually necessary.   This has made Cheetah feel much safer
and more confident.  I also make sure that Panther doesn't steal all the
toys.  Depending on the mental attitude of the cat at any specific moment, a
soft toy may either represent a kitten or (more usually) a prey item, so
they are significant possessions.

The fact that Kali is starting to bond with you, suggests to me that you
dish out the cat food, and this is a very important lever.  Whenever you put
their food down, say "this is Kali's dinner .. this is Midnight's dinner".
In this way, you are reinforcing Kali's place as top cat (or alpha female).
She will appreciate this, because she's clearly feeling displaced at the
moment.   The fact that you're already annointing them with scents (other
than their own) is great and shows you have good insight.  Keep up with this
and, perhaps, add catnip to the scent menu, especially when you introduce
them.  When you introduce them, close all the doors and windows to that
room.  However, because they then can't escape each other, make sure you
have a few boxes or other hides that they can use as bolt holes if
aggression mounts.   I have mixed feelings about the use of leads during
introduction: on the face of it, it seems a good safety ploy; however, it
may down grade any progress you make because it's so unnatural.  The cats
need to work it out themselves.  It will, as Bill says, take time.

Another thing you can do is praise the cats whenever they meet but don't
spit or fight; similarly praise them for simply ignoring each other.   Also,
when you're at home moving from room to room, and the cats follow you, make
sure you always push the door wide open so that there's no opportunity for
conflict at the threshold.  Cats *hate* confrontation and find it
threatening, so anything you can do to prevent confined head-to-head contact
or aggressive staring behaviour, the better.

And to answer your final question, they will eventually tolerate each other
but there will always be spats and disputes.  Life will become easier, and
your job as arbitrator will become less stressful, but you'll never be
redundant!

Do let us know how you get on.
Spider

Thank you Bill and Spider for all the helpful suggestions. I often don't
know the best way to approach a situation and sometimes make the wrong
decision ... but practice helps and hearing the experience of others in very
valuable.

I have mixed feelings about several things also ... Each of the cats has a
bedroom in our home that they can claim as their own ... This seems to be
the only answer right now. I am petrified that the new cat, Midnight, might
be injured. Kali acts like she is ready to eat her alive any time she sees
her. I have NOT allowed them in the same room together yet. Kali snarles and
hisses and even seeing Midnight through a window sets her wild. Kali is not
a friendly cat in her best moments. Midnight appears terrified of her.

Both of these cats have been spayed, so there is no possibility of kittens
for either of them.

I've had many cats over the years, but never a problem like this one ... For
now, they are taking turns being in the main part of the house with the
other being in "their" own room. This works fine, BUT, is not the permanant
answer as we do want all our furry family to be able to share the same space
...

I'll let you know when and "IF" I get up the courage to try allowing them in
a room at the same time ... Wish me luck.