Apple Doesn't Fall Far - HP

Thea Black, daughter of Sirius Black, starts her fifth year by having to split up a fight between two third years. Thea wants to prove to everyone that she's more than the daughter of a supposed killer, so she pushes herself to advance her knowledge. She's completed classes high above her peers level, because of this she's teaching herself at a seventh year level, and has many free periods as a result. During one of her free periods, is when she splits up the fight and meets two young wizards who both have relations to her.