A twist in the tale (Harry Potter Fan Fic)

What would you do if you found yourself dropped into the world of Harry Potter?
Years have passed since the battle of Hogwarts, our hero's are older and their children are now at Hogwarts. But when someone from our world falls into theirs, what will happen?
Georgia is just a normal girl, who hates maths. But when she finds herself in the world of Harry Potter, is it real, or just a dream? And now she's meant to help protect the school from an old evil... will she decide that its not a dream?

I DO NOT OWN MANY OF THE ORIGINAL HARRY POTTER CHARACTERS WHICH BELONG TO JK ROLING EXCEPT GEORGIA AND OTHER INVENTED CHARACTERS