What...I DONT FART IN MY SLEEP DO IT???????????

Of course you fart in your sleep, everyone does. Especially if you're holding it in during the day, you're definitely going to fart more at night. Your body is allowed to relax at night when you're sleeping, therefore, the gas that has been building up in your intestines releases when it is relaxed. It's normal. You don't need to set up a tape recorder, unless you want proof that what your little sister is saying is true. You know she does it, why would you think that you don't? Don't take any medicine to suppress it, you don't need to.