When I was four, I took my shoes off under the dining room table and ran into the kitchen, the floor of which had just been polished. I slipped and fell head-first into a corner where two walls met. Blood spewing everywhere, my older relatives fainted, my dad scooped me up and got me to the hospital before I bled to death. Still have quite a scar. Apparently didn’t affect me cognitively! (Though some might disagree).