My girls got a Disney Story book (the ones with a bunch of different story's in it) and had them sign at the end of their story. So when we read from it and get to the end we talk about how we got to meet them. My girls love it. Not all of the characters are in the book so we also had a scrapbook, had the character sign on one side and put a picture on the other side. It was fun to make and now to look back on the trip.