I always knew the girls absorbed background noise. We always have music on at home. Whenever we start playing new music, the girls start singing it after a few days. When we're in the mini-van, we tend to listen to what they call "our" music. Most of it is typical kids stuff, including our favorite Kindermusik cd's.
Yesterday we were driving back from the grocery store when one twin said to the other one, "Why would you find a naked body in the forest preserves?" Her sister said, "You'd be cold." I froze. I forgot I was listening to news radio when I was alone on the van. When we started driving home, I forgot to put on the kid music cd's. I pushed the cd button and more appropriate sounds came out of the stereo speakers.
I made a mental note to be more careful in the future.