That I don't know exactly if it's just one on one, as I've not read up on it when it's a more personal relationship.

I do know that my own wife, who was home all day watching just one child, was open to taking on more for free, but regulations around it made it way more of a headache than it was worth. There are laws about how many kids you can watch, how long you can watch them, licensing, child to adult ratios, state visits, etc.

Basically, if you wanted to be open to watching 5 kids for a working day, doing so would be illegal in every state I've lived in.

Every state has regulations and laws that at face value most people would agree with, but together end up in a system where you have to pay thousands per month for a facility to watch a child.

> If you leave your kid with a friendly neighbor

That's perfectly legal where I live, but... There are no friendly neighbours with that kind of time on their hands. My entire townhome complex of 34 units (ranging from 2–4 bedrooms each) has only one single elderly woman who's retired. Everyone else is young people in their 20s (working), or families with their own kids and—in all families but one—two working parents.

Probably only kicks in for paid providers. There would be all sorts of laws around safety (making sure the areas are child-proofed, no dangerous items (knives, guns, medicine), background checks, temperature maintenance, emergency plans, etc.).