They're going at it hot and heavy.
Suddenly they hear a noise.
It's their little son Timmy, standing at the door.
Timmy's shocked and runs out of the room.
The father goes: "I'll talk to him."
He goes to Timmy's room, he opens the door, and sees to his horror how little Timmy is giving it hot and heavy to grandma.
The father goes: "Oh my god!"
And little Timmy says: "Not so funny when it's your mother, is it?"
Now is just right now.