ohhh 80's theme sounds great. Maybe set up a "big hair" station. Where are have combs, brushes, tons of hairspray. Treat all he ladies to the 80's "big hair" do. Also, try a used CD shop (if you don'r already have them) for cd's such as Whitesnake, Bon jovi, Poison, Kiss all the big 80's bands to play in the background. Invite everyone to come in their 80's band T-shirts & ripped up jeans. Hope some of this helps & have a great time. It's so nice for you to do this for your sis