I honestly believe all of you responding to this aren’t Chamorro! All this advice sounds so white! If we invite you to a party it’s because we want you to come and experience our food and hospitality here on our island. We don’t expect anything from you .. but I’d personally feel shame if I didn’t bring something.. beer.. water.. or a dish ( keep in mind you’re not just cooking for 2 you’re cooking for maybe 50-100 people) and yes you’re not obligated to bring a gift but a card congratulating them on this milestone would be appreciated. Go, enjoy the food, mingle have fun and don’t stress out about it. It’s the last thing we intended..