When I was ~5 years old and my brother ~6 we were in the living room when my mother put a box of matches on the fireplace and told us not to play with them.
Her heels had barely passed from view when my brother snatched the box and had me follow him outdoors.
Behind our house was an empty field, many acres worth.
We went a short distance out into the field (as in less then 10 feet) and he stared lighting matches, dropping them, and then we would both stomp them out.
There wouldn’t be anything to write about if nature hadn’t taken its course and spread the fire. We stomped and stomped yet it kept on spreading.
My brother told me to run into the house and get a blanket and toss it out the window. About the time I was throwing out the blanket (we had a window that looked out towards the field) he had come to the house for it.
I joined him back out in the field where we spread the blanket over about a blanket’s worth of ground and kept stamping all around on it, occasionally peeking beneath to see if the fire was all out.
Somehow we got away totally clean on that one.
inarguable 
Ah, so you don’t remember the fire marshal coming to the house. I was 8 and I do remember.
my memory of the incident centers on observing the smoke.
I believe fear of punishment was the main reason for it sticking with me.