Ah. Perhaps.

My family was out of town last week, so I was home alone. It was fine, but nighttime was weird because it was so quiet and lonely. And I'm not going to lie-a tiny bit scary. Anyway, I woke up in the middle of the night and thought I had heard someone doing our family's "secret knock" at the inside door leading to the garage. At first I thought it might be Grandpa Elison, but that didn't make sense because it was like 3 AM. So, in my half-asleep little brain, I concluded that it must be some scary person trying to get in by pretending to be grandpa (by doing the secret knock). I determined that I would not answer the door, and I promptly fell back to sleep.

I have been reflecting on the absurdity of this experience, and I finally realized where that all might have come from.
Have you all read this "children's book"? Because I remember that it terrified me as a child. Anyway, my experience kinda reminded me of what happened to the girls in this story. You should all read the book.