Ideas for planning pre wedding celebration for brother

Myself and my siblings decided to get our own rental for our little brother’s wedding, no parents, just all the kids hanging out together. Our brother that’s getting married asked if he could crash at our rental the evening before the wedding, and we of course said yes (he’s doing bachelor party stuff a few days before the wedding, so he has no night before plans).

We’d like to do something celebratory for him since it’ll be just the siblings all together. He’s our first sibling to have a proper wedding and none of us are really good at planning events, so beyond sharing a nice bottle of booze, we’re not sure what else we could do. Got any ideas for a nice send off sort of thing? Thanks!