Great advice above! Hope you have a wonderful time!
Few more from me....
Play with the kids. Dance with them. It can be scary for kids when the adults around them are drunk, imo. They want someone clear-eyed to play with them, help them get food, get them a drink, and take them to the restroom.
Practice for the UH-OH moments....like shots being lined up on a bar or on a tray. You don't have to drink anything even if it's sprung on you! You could even "accidentally" spill it!