There are rules. We meet the requirements.
And then there's the cultural requirements. The 9 year olds have to be able to talk the 7 year olds into experimenting with diddling on the fence, without killing the 7 year olds
NOTICE!
KEEP THINGS SAFE! DON'T PLAY WITH WATER(OR OTHER LIQUIDS) and ELECTRIC FENCES!
NOTICE!
I've told 'em. They won't listen.
Been there, done that.
I lived.
/johnny