I'm going to have all of my sisters in my wedding party except for one
Why are you excluding one of your sisters from your wedding party?
Her behavior is inappropriate and difficult to control.
I'm sure your sister's behavior is difficult to deal with but you shouldn't exclude her from your wedding. Talk to her about her behaviors and explain what your expectations are. She may be willing to change so that she can be included in your wedding.
You are right, she might be willing to change.
that is good that you are going to give her a second chance to be a part of your wedding.  I'm sure she wants your day to be special as well she might embrace the chance to change.