My cousin has 8yr old twin girls. She made a very realistic poo, out of Nutella, which she left lying around. When they got up, she asked which one of them was responsible. Obviously neither of them owned up, so she told them the only way to tell which one of them did it was with a taste test. And ate the 'poo' in front of them.
Pretty sure they're gonna need counselling for years, but fucking hilarious!!