A Halliwell at Hogwarts: The Prisoner of Azkaban

Great! Her third year hasn't even started and Persephone has already a new worry in her life!
She can't believe it. Her uncle has escaped Azkaban and she can't help but wonder what will happen to him if he's caught.
How will Harry, Ron and Hermione react to her connection with Sirius Black?
How will the same Sirius react to the discover of a niece?

DISCLAIMER: I don't own Harry Potter and Charmed, but only my OCs and the modifications of the original plot of the Harry Potter series. The credits go respectively to J.K. Rowling and Constance M. Burge. Furthermore, unless I state otherwise, the images used in the chapters belong to the respective owners.