Ohhhh when my nephew was like 4 or 5 I babysat for the day, and he fell off skateboard and broke tooth out! I felt horrible, but I still bring it up today, he's 23 now lol and he says it wasn't your fault I fell. ;)
My babysitting fail: Was whenever my aunt would have to go grocery shopping she would take me with her so I could sit in the car with her two hyperactive kids. Well one time the 4 year old was peeling the wood veneer finish off the steering wheel in her car. I told the 4 year old numerous times to stop peeling the finish. She would not listen to me. So I just let her and waited for my aunt to come out of the supermarket. Well she finally came and I told her what her daughter was doing and she got so mad. But not at her daughter at me. I wanted to cry because I tried to stop her but she did not listen. So that was the worst thing that happened to me as a babysitter. "Getting in trouble"
Thanks for the comment, love!!