So, last night, I'm sound asleep and hear knocking on my front window. Three fairly loud, quick knocks. I get up, turn on all the outside lights, there is nothing there.

My husband didn't hear it at all, but about a year ago, he heard the same thing and I didn't.

Anyone have any ideas? I know what I heard, it got me out of bed. I had a hard time getting back to sleep (it was 4:00am).