I'm going to Paris and Rome . . . sort of!

My dear sweet friend is taking her two daughters on a trip to Paris and then on to Rome. Naturally the occasion called for a card to wish them each safe travels. But I also had an ulterior motive. By my thinking, if I made them each a bookmark to slide in a book they will no doubt take along to help pass the time on their flights, in a very real sense, I would also be making the trip with them! My only concern is what if they misplace their bookmarks, does that mean I won't get home?