First Cat Afraid of the rest

pepper my original cat, is afraid of all the other cats, even though she is larger than the kittens......i dont know why

Because in 'Catdom' instincts are telling her that as the oldest cat, she's going to be under attack from the others trying to be #1. It happens in all cat hierarchies and there is very little you can do but try and protect her from the others. I've gone through it numerous times, and sometimes the best thing is to help her find a high place in a corner that she can easily get to, with bedding, where she can hold off the others when they've chased her there, and possibly in a room with her own box (probably won't last long as her own, but...) and after she uses the box, or after feeding, make sure they don't chase her (for some reason those are common chase times). Also use Feliway plug-ins because they should help, and just keep a close eye on things. Try to distract the younger ones if they take a bead on her (it's what they do) before attacking. It's one of the few things about cats that make me angry even though they're just being instinctive.

We have been using feliway for a while, thanks for the tips!

Does Feliway seem to be helping?

I knew a massive cat that was terrified of kittens. He was sweet and loving, got along well with adult cats, but cowered from babies. It could be a personality thing. Is he from a feral/stray background?

What is the status on al the cats? Age? Sex? are they all spayed or neutered? That can be a big factor in it and the first, easiest step to trying to fix the problem. It isn't really a problem, all cats need to establish who is alpha.

How did you introduce them all? Did you just plop all the new ones down in front of the original one? That is the WRONG way to do it and if that is what happened, then you need to read up on how to properly introduce new cats to the home.