Introducing cats to a new kitten!? Help! ?

[Michaela S]

Okay so I got a 7 week old kitten a couple days ago and it's not going too well! Okay so we have her in a separate room( my room) with a scratch post, litmassageplanetug , food, water, her bed and she is slowed on my bed! Oh and also toys! She is alowed out of the room with a family memeber we just keep her away from the other cats! She gets along great with my small dog and they love each other already! ( my dog always sleeps with her and they are in the room together all the time! Anyway I have 2 , six year old cats who HATE other cats! They are extremely grumpy! And 1 cat who is about 1 year old, he still acts like a kitten but hates this one too! We introduced them one at a time and each one of the old ones hissed and hit the kitten! Now we are scared to introduce them again because she is so small we don't want her to get hurt! The other cats were not too thrilled when we brought the one year old in 9 months ago and they still fight buy he can protect himself , this one can't! Tips? I don't want any of the to get hurt! Thanks