Bridget (author of The Unauthorized Legoland Guidebook) offers this common-sense travel tip:
This is an oldie-but-goodie so you may already know about it, but I thought it might help someone. Take a picture of your kids with a digital camera BEFORE entering an amusement park […or sporting event, or zoo, or any other crowded place — Ed]. That way if your child gets lost, you can show theme park personnel EXACTLY what he or she looks like including hair color, eye color, and clothing. With two preschoolers who sometimes go in different directions, these pictures have come in handy. You also have a fun “on our way” picture to add to the scrapbook.
Related: The now-famous travel ID hack: Sharpie your cell phone number on your kid’s belly