Dub, I am *old-school* too.....get off your A$$ and get a job...steal $$ from your mother???? no way, no how!...my daughter was 26 and i told her in no uncertain terms..."you are off my payroll"!
my daughter stole $$ from me too....got a cash advance on one credit card I allowed her to use for school...then she changed the address on the card, so I did not get the bills....SIX THOUSAND dollars later, she tells me she can't pay it.....OY!!! I could have danced on her head...I paid the bill, removed myself from her finances and let her flounder.....I could go on for 20 paragraphs, but I do not let it bother me anymore, my locks are changed and she knows there is no way I will finance her.
I hope you and your wife nip this behavior and it is a one time incident....I think taking a firm stand on driving home integrity is something man of our kids don't understand.....they live off of our hard work.
good luck, it ain't easy!