Little Johnny woke up in the middle of the night and decided to get a glass of milk.
He walked past his parents room and heard some noises so he decided to open the door to see what was going on.
Little Johnny saw his Dad on top of his Mom and asked "Dad what are you doing"?
His Dad said go back to bed son you are just having a dream, then he looked at the mom and chuckled because he knew that they had been caught.

The next day Little Johnny's Dad went to go tell him that dinner was ready but when he opened Johnny's bedroom door he had his Grandmother bent over the bed banging her in the ass.

The Dad screamed at Johnny! "WHAT THE FUCK ARE YOU DOING"!!!

Johnny smiled and said "Oh I guess it isn't so funny when it's your Mom is it"???