A Nickel for that tear

... a cut on the foot brings a tear to the corner of Rhiannon's left eye ...

When I was young, I was  promised a nickel for every tear that I could catch in a cup.

Mary told me that with inflation, that price should be going up. True, but there is something that catches the idea my personal heritage in that phrase "a nickle for every tear....".

There are other phrases from my childhood that have numbers in them, numbers that I can't verify using academic records.  Take for example the sentence, "You have to wait 24 hours before you can play a trick on someone who has just played a trick on you."

Where did that number come from?

Arta