You may wonder what the logic is behind a patron's order of operations

The Story:  I was at the reference desk in the evening, by myself, about an hour before closing time.  I get a call from a mother, looking for her child that she's supposed to pick up here.  Now, the teen and adult areas are on the same level, so I expected the child to be a teenager.  I paged the name she told me, and when no one came to the desk, I got back on the phone and asked for a description.  I then find out she's looking for a nine-year-old.  Armed with this new information, myself and another librarian who was technically off the clock -until he heard there was a missing child- went on a search of the entire building and grounds.  After no such child was found, I get back on the phone with the mother, who requests I page her son again.  I do, to no avail, and we go searching the library and grounds again.  The following conversation then takes place:
Me:  I'm sorry, but we can't find anyone matching your son's description anywhere in the library or parking lot.
Her:  Oh, this is not good.
Me:  Does he have a cell phone on him?
Her:  Yes.
Me:  And I assume he's not picking up when you call him?
Her:  I actually haven't tried calling him yet.

Image credit:  Stolen from the Google; Sorry.

The Lesson:  Do I even need to say anything?  I mean, why bother giving your 9-year-old a cell phone if you're not going to use it?  The only lesson I can get out of this is don't be afraid to ask what should be a stupid question, and ask it early so you don't waste nearly half an hour of your time looking for someone you'll never find.  We never did get a call back from the lady, so I'm presuming she found her kid.

The Resources:  I can't honestly even think of anything that would be helpful in preparing for this situation, or dealing with it.  If you can, feel free to share them in the comments.