This is a true story, according to my sister. Although I do not remember this. My sister shared this story during her toast to me at my wedding reception. I do not think I've ever laughed so hard in my entire life.
According to my sister, when I was around 9 or 10, and she was around 7 or 8, I sat her down on her bed and we had the following conversation:
Me: "Do you know what sex is?"
Heather: "Nooo. . ."
Me: "It's when Dad puts his penis in Mom's vagina!"
Heather: Painful, stunned silence.
After about five minutes of my letting this information sink in, I then add, "And there's no Santa Claus, either!"
My poor sister insists that Christmas was never the same for her after that.
But I am the older sister -- it was my job to share such knowledge with her.
Merry Christmas! (And Heather, I'm really, really sorry I did that to you!)