Who Pooed In My Loo

In the bathroom this morning, I looked in the loo, and guess what I saw - yes that's right, it's a poo! I couldn't believe it, I called for my mum, There's a gift in our toilet that's made by a bum! When a little boy finds a poo in his family loo, he starts imagining who might have left it there. Was it... A dragon? A unicorn? A dinosaur?! With every idea more exciting than the next, he can't wait to find the culprit. But who could it be?