You might want to put a divider in their brooder box- separating the ones being bullied from the bully + 1 or 2 that are not being bullied. Make sure they can still see each other though. Then after a few days try reintroducing them
my last chick who was named dixie was doing that for about 2 weeks and died. but this could not be the case, i read on the internet about something called chicken jail. its when you take some chicken wire and put in in thebbrooder seperating the chicks. this may work and also it may turn out to be the scenario of my chick..... does she gett pasty butt alot?