The Family Photo That Was Left on the Surface of the Moon

We've seen photography of the Moon, and photography taken on the Moon; people have even left photography gear up there. But this is the first we've heard of a photo from Earth, not only making it to the Moon, but staying there.

Fortunately, it was left there on purpose (Can you imagine? "Uhhh ... John ... we need to turn around, I forgot something..."), and the story behind the picture goes something like this.