My dad is a huge prankster. When I was about 5 or so, he started telling me that he was part of Witness Protection, and that he had to start over with a new name, new home, new family. Apparently, this really bothered me, so (of course, what else would a great dad do? lol) he continued to embellish the story. He made it more and more detailed throughout the years. And when I was 10, I finally asked him when I could meet my real family. I've never seen him laugh so hard.
I also knew about sex from the time I was 5 (my older sister was doing it and told me everything). While in the bathtub, I would stick my finger in my butt, wondering if that was my vagina.
Not me, but funny nonetheless. My little sister was about 6, and my little brother was just barely talking. He was on this kick where he wanted to watch Austin Powers OVER AND OVER on repeat (I guess cause of the bright colors). So sister asked him what he wanted to watch. He started jumping up and down, screaming, "Ottin Powa! Ottin Powa!" She put her hands on her hips and said, "No, Karl, we are NOT watching the fat bastard again!" My stepmom came running into the room, yelling, "Sally Renee! We do NOT say that word in this house!" Sally started crying, and said, "I'm sorry, Mama. I'll just say "chubby."
*names have been changed