I know a couple of people who permanently negotiated 4 day working weeks after becoming parents. One of them has his daughter at some sort of parent run day car

I know a couple of people who permanently negotiated 4 day working weeks after becoming parents. One of them has his daughter at some sort of parent run day care, where each of the parents spends one day a week staffing it, so they all work 4 days (at most) and spend at least one day looking after all the kids.