When I was around 13, my neighbor Dixie and I were fucking in her bedroom. Her mom walked through the door, saw what we were doing. She just said "sorry", and closed the door. Mom told me years later Dixie's mom was the town cum dump when she was growing up, so Dixie came by it naturally.
I started to notice that after our oldest daughter, eleven at the time, was done with a shower, there wasn't any hot water left since we installed the hand held shower back in the late 90s. She never thought that I figured it out LOL 😆