[ WP ] Every night for as far back as you can remember , your parents have given you a new mystery to solve , but tonight is different . Tonight your parents have vanished without a word .

`` And that's why I have to solve this mystery!'' I said to Uncle Aaron. 
 
 Uncle Aaron looked back at me. `` How old are you?'' He asked. 
 
 `` I'm ten,'' I said. With his memory, I suspected the question was not rhetorical, though this was possibly also because I'd only recently learned the word'rhetorical'. 
 
 `` Ten. Your parents should have already talked to you about this,'' he said. `` Listen, parents sometimes need time to themselves, you understand? So they can, you know... be in love.'' He was clearly skirting around some particular topic. 
 
 It did n't matter. `` But it's a *mystery*!'' I said. `` They're giving me mysteries to unravel so that I can one day be the greatest detective ever to live.'' 
 
 Aaron looked like he was torn between being direct and being gentle. He opted for the latter. `` Okay, do you remember the Mystery of the Banging Wall?'' 
 
 I nodded. I was almost certain it had been ghosts. My parents had been looking for them under the covers, for some reason. 
 
 `` And do you remember the Mystery of the Blocked Bathroom Door?'' 
 
 I had - the bathroom door had a strange property that sometimes, in addition to being locked, it would get strangely heavy. As though something had been placed in front of it. Or, possibly, a ghost had been keeping it closed. 
 
 `` And the mystery of the Steamed Car Windows?'' 
 
 That was the most obviously ghost-caused case I'd ever cracked. 
 
 `` What do these have in common?'' Uncle Aaron asked. 
 
 `` Ghosts.'' I answered, matter-of-factly. 
 
 `` No,'' Uncle Aaron had his palm on his face. `` Both your parents are always there at the time, are n't they? Under the covers, in the shower, in the car. They're *both* there. And seemingly trying to keep others out. You understand?'' 
 
 I did. `` So the ghosts can only haunt *both* of them!'' 
 
 Aaron gave up. `` They're having sex, kid! Sex! With each other!'' 
 
 `` Oh.'' I said. 
 
 Aaron nodded. 
 
 `` Oh....'' I continued. 
 
 Aaron spoke up. `` I hope this realization means you'll fully understand the joke I am about to make.'' 
 
 `` OH...'' I said, fully understanding the true nature of all the mysteries I'd unraveled. 
 
 `` That,'' Uncle Aaron said, `` is what she said.''
