here is another tip...i have had this happen to me 2 different times...once in chicago with a film camera and once in disney...
if you are at the end of the roll of film or if you only have a few more pictures left to fill up that memory card, before you really get involved in something, change them out!!! put a fresh one in...
in chicago, i had my camera, with a roll that included my son's 3rd or 4th birthday party on it. i only had a few more to go, but since we were in chicago and at a wedding, i figured i'd just change it later. well, at the church, i didn't bring in my camera, since you aren't really supposed to take pictures of the ceremony...well our rental car got broken into and my camera was stolen.
then in disney, my digital camera was left in a bathroom (by my son) and we didn't realize it until an hour later. it was of course gone. i only had about 15 more shots to go...my sons had just gotten their hair cut on main street and had color gel and mickey confetti sprinkled in, and they all were gone!!! 2 1/2 days of pics in disney...all lost...and go figure, that was the first trip where i only brought 1 camera!!! i wanted a more current digital, but what a way to have to get one!!!
this is what i have learned, film wise....i always put one of those self adressed self adhesive return address stickers on my rolls of film. that way if one is ever lost, hopefully some kind person will send it to me.
or, i have never done this, but i have heard that some people have an index card that they just put in their camera bag, with their name, address and phone # on it...when you change your roll, take a picture of that card so that the developer will know the owner of that film if it ever has gotten lost in developing, or if somebody else has picked it up.