I'ts funny what you can sleep through. My parents woke up one day to hear a radio news report about a police chase which had involved a fleeing car trying to shake the police by driving through back yards in XX subdivision. My parents said, "wow, that's our subdivision, I wonder where it happened?"
They looked outside, and found multiple tire tracks dug into their own yard, making a "U" shape right around three sides of their house. (They live on a corner near a dead-end, the perp found himself boxed in and had to use their yard to backtrack.)
There was a huge patch of bark several feet in diameter entirely missing from a big maple tree about four feet from their bedroom window, it must have made a huge noise when a car sideswiped it, not to mention the roar of engines and probably police sirens, but they slept through the whole thing.
Now I cannot even go to bed if we have a strong chance of bad weather during the night. One night I stayed up waiting for a cold front to pass and I saw bright green lightning!
Oh my, lol, that's crazy...maybe you and my husband were switched at birth - sounds like your parents should be his. He sleeps through everything! Children crying, phone ringing, wife beating him with pillows, shoving him as hard as she can...
A couple months ago some very severe thunderstorms came through in the middle of the night while half my family was visiting, wind and thunder so strong the house shook and banged like someone was beating it with a giant frying pan. Woke up everyone but him.
No doubt someone drag racing on the lawn wouldn't roust him either. :)