I guess I'm lucky I work at home. Today, during a meeting, Aidan alarmingly told me "Dad! The toilet is overflowing!"
It was the upstairs toilet, right above the kitchen. Not only was the upstairs bathroom flooding, it was raining toilet water in the kitchen, leaking all the way to the basement.
To top it off, the shutoff valve by the toilet would not turn. I had to reach in the tank and stop the water inside the toilet. I'm going to test all the shutoff valves in the house. (Shouldn't the home inspector have tested these?)