Hmmm. Aside from NOT wearing white, there are really no other protocols or traditions worth following unless you really want to. Don't your sisters have kids of their own to marry off?
(It's times like this that I'm glad I don't have sisters!!)
I thought not wearing white was about it, too, but there's the rehearsal dinner for one. I'm now giving the bridal showers for our side of the family.......one of my sister's suggested that. My one sister has 3 out of 4 married and KNOWS everything!!!
I'm guessing your sister is having a great time spending YOUR money. Sorry that you have to deal with all that. But it really isn't a wedding without family drama.
Kitty - Sounds like a "whole heap of nothing over somebody else's idea of something" as a relative of mine used to say! Don't you love all the wedding traditions?