Scarred For Life.

Warning - link has some profanity.

http://my10kidfamily.blogspot.com/2005/04/my-mom-and-dad-did-it.html

My mother was a single mom, who rarely dated, so I was never traumatized in the above fashion, BUT that makes it all the more amusing.

I had a friend whose parents would always make her and her siblings watch Saturday morning cartoons. The parents would emerge from their bedroom towards noon, wearing matching robes, and all a-glow. One day it occurs to Corey: "Oh My God, these people are having sex." After that even a glimpse of the robes filled her with angst.