My mother cat of six one-week old kittens is avoiding nursing her kittens, but will carry one particular kitten off into another room to feed. Is there something wrong with momma or this particular kitten, and how do I get her to feed them all?

Well Why don't you feed the cats that she tends to avoid ?

My mother cat of six one-week old kittens is avoiding nursing her kittens, but will carry one particular kitten off into another room to feed. Is there something wrong with momma or this particular kitten, and how do I get her to feed them all?
Try putting the kittens onto mum nipples yourself

Is this her first litter? It is possible she doesn't know how to act or what to do.
Or there could be something wrong with the kittens.
Get her spayed to avoid problems like this in the future.