Bebe, your article is great. Understandable and complete.
I'm wrestling with this problem now.
I look at it thusly: I've seen kids robbed of their abllity to "make it on their own." How shortsighted of parents to do that.
However, the reassurance that you'll always "be there" for them financially as welll as emotionally is a must. Emergency's are meant for you to step in as a financial resource when all else is exhausted.
If you're called upon (or better, step in and offer) don't expect it back. If it is returned. it's a bonus. It's not worth the family disharmony unpaid debts engender.