Introducing New Cat

I need some kitty help: I have a 5 year old cat and am introducing a new little kitten to the home. They have seen each other (she in a kitty carrier) in the same room. Been taking it very slow, the kitten has been with us for about 3 weeks & they've never been face to face yet w/o the carrier. Tonight, the older cat attacked the kitten under the door of the room she's in, hissing and going for her exposed paws under the door. I am terrified we are going to have to give the kitten up and do not want to do so. What can I do to help this work out. Please give any and all ideas, thanks.

First off, you need to start with scent swapping and then possibly room swapping.  Take it very very slow.  Cats are territorial by nature and the new kitty is upsetting the apple cart.  Most of the times cats can learn to coexist and even be buddies.  But it doesn't happen overnight.  It takes a lot of work.  You need to be sure the kitten is safe.  How old is the kitten?  It might be that you need to wait a bit.  You can definitely allow the kitten out with supervision as long as the resident cat is put safely away.  This too will allow the scents to mingle.  Do you have any feliway plug in diffusers?  These are tremendously helpful.  Yet be sure you have them in different rooms.  One is often not enough.

Here are some articles to read and a video to watch on cat to cat intros.  Just take it slowly.  I mean really slowly.  The entire process might take months.  It took my two one solid year to coexist.  Yet it does happen. 

http://www.thecatsite.com/a/the-ultimate-yet-simplified-guide-to-introducing-cats

http://www.catbehaviorassociates.com/a-simple-little-trick-to-use-during-new-cat-introductions/

http://www.aspca.org/pet-care/virtual-pet-behaviorist/cat-behavior/introducing-your-cat-new-cat

http://jacksongalaxy.com/2010/10/01/cat-to-cat-introductions/

This is extremely helpful! Thank you for posting all of this! Appreciate it

Oh, the kitten is tiny, she is about ten weeks old.   I will get some feliway, great idea!

A couple of days before the "attack" the older kitty laid on the floor and rolled around in front of her. Does this mean what I think it means (trying to be friends?)

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