My BIL basically works just enough hours for health insurance. My sister makes the bulk of their household income. He always wanted a managerial position but the hours weren't flexible enough so he said he'd wait until my youngest nephew started school.

Some court decided that the lack of positional flexibility was sexist and unfairly penalized mothers with kids so the company eliminated the limitation of choosing your own 40 hour workweek.

After that my BIL got a raise and a promotion.

Thanks Feminism.