I could write a long essay but instead I'll give the cliff notes.
Son (young 20's, no debt, savings, paid cash for used car) marries woman with issues but he loves her. His call. He has a strange inability to say no to her and she introduces him to spending. It's like watching someone go from a gateway drug to harder stuff as they buy all kinds of crap including starting a collection of old video games. He's in the service and they have a new child, he's getting out in a few weeks without a solid job lined up, AND THEY BUY A NEW CAR.
DIL quote #1: "We bought it now because we know that no one will finance us once we get out of the military in two weeks."
Evil Manipulative Mother In Law (EMMIL) had visited for the birth of the child (staying in our home for 3 weeks) and now she begins an intensive campaign of manipulative emotional hostage taking along with outright factual lies to get the young family to move across the country to be closer to her. It works, and they spend a crap ton of money (financed by selling son's paid-for car) to move to where education and job prospect pies-in-the-sky have been promised by EMMIL. More poor financial decisions on housing (a too big house is rented), schooling (GI Bill tuition wasted), training for non-existent job prospects (lies by both PIL), etc. etc.
Throughout this debacle we have offered our opinions when asked, sometimes not when asked, and then shut our mouths and watched the train wreck. DIL has consistently ignored us and instead acted on her mother's advice.
Young family finally clues in about EMMIL and moves 5 states away, both taking low paying jobs but getting away from the poison.
DIL quote #2: "I guess we shouldn't have been taking financial advice from people [her parents] who have been bankrupt four times."
[And ignoring advice from her parents in law, us, who paid for college for kids with no loans required, have paid off their mortgage, have zero debt of any kind, and can retire any time they please.]
They finally start listening to us and opening their financial books. Tons of debt (half student debt brought into the marriage), a monthly cash flow of -$500 and no way to fix that, behind on rent, utilities, etc. They'll be living under an overpass in 6 months.
We bail them out enough to bring them home and get them into a living situation. Son gets job and starts looking for a better one. DIL re-passes her state boards and starts working part time. They start listening to us on money. A decision is made to not declare bankruptcy. They work out repayment plans with creditors. Credit cards save one are paid off and they're working on the last one.
And, lo & behold, it's DIL who has taken charge of the family finances and is doing all this. There have been a few relapses (a $200 Christmas gift for hubby) but, by and large, she's shopping at thrift stores, clipping coupons, accumulating a small emergency fund, etc. etc.
DIL quote #3: "I think in a few years we'll be able to start saving for a down payment."