I often would baby sit my sisters and brother for short periods of time when my parents went away. One night they left me babysitting while they went to a movie which was very close to our house. After my siblings fell asleep, I lay down on the couch and soon fell asleep also.
When my parents arrived home, they were locked out of the house and they knocked on the door to get inside. I didn't wake up. They called out my name to me, I slept on. They continued calling out my name and then banged on the window. I didn't respond. Finally they went to the guard house and had the guard call our house. I'm told the phone rang for several minutes before I woke. My reputation for sleeping through anything continued.