Noises upstairs

I hear noises upstairs a thump and some moaning. It's not from the direction of the master, which should be the only couple in bed together tonight. My curiosity gets the better of me and I head up the stairs. When I get to the top of the stairs I realize that the sounds are coming from the twins' room. Sara and my wife should be in there. Maybe Sara's boyfriend got into town early. Something tells me that's wrong though. For some reason I have a knot in the pit of my stomach as I walk to the door to the twins' room and I turn the knob. I open the door and even in the low light coming from the moonlight streaming through the window I can plainly see Kenny between my wife's legs. His bare butt is thrusting repeatedly towards my wife. Megan's eyes are closed and she's just laying there and moaning.