"knock knock knock"

Here is one of the more recent ghostly encounters my dad has experienced at his house.

Late at night, he was sleeping in bed, and he kept hearing a very distinctive knocking on the wall. I've heard it too before- I always dismissed it as an animal in the attic/wall, or maybe a branch scraping against the house. Anyways, this was coming from the side of the house were there are no trees near the house, or really anything.

Anyways, he keeps hearing these sounds, knock, knock, knock... and they seem to be pretty rhythmic. My dad, feeling ornery, decided to knock back.

the wall went "knock knock knock!"
My dad echoed the same pattern.
The wall knocked the same pattern again.
So my dad knocked: "knock knock... kna-knock"
and seconds later the wall answered the same back!!! It repeated his pattern!

My dad decided he had enough of teasing the ghost that night, and went downstairs to sleep. :D