Thanks, this makes the most sense. However, I do wonder if there is a difference between playing/teaching nieces and nephews that you can hand back any time, and doing it all the time. Kind of like the difference between visiting a place as a tourist and actually moving to live there.

I would probably want to 'borrow' some relative kids for 2-3 weeks while they go on holidays, and see how the whole thing works - not just the fun parts - before I would be willing to commit to it. I do not mean you here, but it always surprises me how lightly people - otherwise very careful and responsible - take the most important and consequential decision of their life.