[Dale Dough]

WTF? Nobody advises revenge? Sure, he won't *need* it in order to get on with is life, but, but, but..

I would definitely not let this go unpunished. People need to know that infuriating backstabbing behavior with childish motives has consequences.

Is one of you scheduled to say something during the graduation ceremony? (I don't remember how many kids get to speak, I slept through mine) That would be a perfect opportunity to embarass that bitch. Doesn't matter what you say or if it's true, if everyone has a laugh at her expense, vengeance is served.

If that's not a possibility, try for something along similar lines. Sorry, can't be of much more help at this hour. Good luck.