Even when she wasn't working, they were investing in retirement for both of them, putting money aside for the kids to go to college, and saving normally. Even if her new salary is "only" $125k or $100k, after taxes, and after new expenses, and after her husband's income, I can believe they would still have $100k leftover total. I missed what her salary is, though.
According to starry in the other thread, she's been talking about 150K job offers. Which, after a marginal tax rate of 35-40% nets lower than 100K. (35-40% is about what Canadian marginal federal and provincial tax rates are, or more). Add in the new daycare, house cleaning, grocery and fancier vacation expenses she mentioned I don't see how she's netting 100 or 125K. Sure, there are plenty of jobs that net that after taxes and added expenses. They pay more than $150K.
I'm just saying that it's already possible they were saving $50k/year before this. Considering her $150k job is apparently just for "fun money," he husband could be making $300k+ for all I know.