[Dementia]

[ QUOTE ]

That's kind of what I'm interested in -- how long can this go on before the giver should morally reveal the gag?

[/ QUOTE ]

Revealing it to be a fake instantly kills the whole purpose of the joke, you should wait until the elation sets in before being like "NOPE IT'S A JOKE", else its a waste of $. So the kid did play the joke out right, it is unfortunate she became so emotional afterward but hey [censored] happens, he doesn't owe her an apology at all.

But obviously, don't wait until she drives down to the local deli or tries to mail it in to collect, but give it a few minutes.