Here's one from sportbikes.net...
Misfire said:My wife and I were setting on the couch a few months ago watching TV. Our Son was in the bathroom taking a shower before going to bed.
My wife looks over at me and says, "Have you noticed that our Son is taking an extremely long time in the shower these days?"
-Me "Yea, he is probably jerking off."
-Wife "Oh, I can't believe you said that, that’s gross!" "Do you really think that is what he is doing?"
-Me "Well yeaaa, he is 13 and that's what 13 year old boys do in the shower."
-Wife "You need to have a talk with him. That is just nasty."
-Me "Ok"
10 minutes later our Son steps out of the bathroom with a towel wrapped around his waist.
-Me "HEY!"
Son stops dead in his tracks while the wife looks on in horror..
-Son "Yea?"
-Me "Your Mom says to stop jerking off in the shower." "She says it's nasty."
Son ducks his head in embarrassment while running through the house to his bed room; the wife tosses a shoe at my head...
His showers are much shorter now...