Wow this reminds me of an old joke:
A man goes to a doctor and says: I have a problem, every time i go to sleep, i get a wet dream.
The doctor says: Could you please explain in more detail exactly how it happens?
A man: Well i go to sleep, and then i have a dream, in my dream a little devil appears and says: Hey, lets go pee! - Next thing i know i wake up with a wet bed.
The doctor pauses, scratches his head and says: Have you ever tried saying "no" to the little devil? Try it!
The following night the man has a dream and the little devil comes and says: Let's go pee!
The man replies: No!
So the little devil say: Let's go poo!