I have a few cousins who are just under 21 (20, 19, etc) and they like to party. We have to hire a police officer to work at our reception because it is at a public park and we are serving alcohol. I'm really worried that the underage cousins will try to sneak drinks. I don't know what the actual consequences will be if they get caught (will they be asked to leave? arrested?? will the whole reception get shut down??). I'm nervous to ask the sheriff's office because I don't want to put them on high alert about it. How would you handle this? I don't think the cousins know there will be a police officer there, although I'm assuming he will be in uniform and they will see him, but would you recommend casually alerting them (or their parents) ahead of time? Or somehow alerting our bar tender to be really vigilant about carding anyone who looks young? Maybe I just have to let the chips fall where they may, but I thought I'd see if anyone had any strokes of genius.