Storm McGonagall: A Hogwarts fanfic: Explanation

Chapter 3! I know it's a little short, but I've already started the new chapter. I also know that you guys were expecting an explanation about Storm's dad and why Professor McGonagall had never told Storm about the wizard world, but I did give two hints about the identity of Storm's dad and one on how she'll discover it.

"You are a witch. I am too. There are many witches and wizards, spread over the whole world, just like there have always been. Some times, ancient times, were good. We were seen as wise people, especially the Seers – the witches or wizards who can predict the future – yes, Storm, they exist. Anyway, those were the good times. The magic people taught their children and life was short, yet good. But then Dark Magic was discovered. Some wizards and witches, the ones who were power-hungry, used it for their own good. The Muggles – non-magic people – tortured us, wishing to find our secret, so that they could stop the Dark Magic. When no one told them, they started burning us – well, trying to burn us. You'll learn about that later. Anyway, we were forced to hide our powers, to live as if we were like them. In the end, they realized that it didn't work, and they ignored all magic things. Well, they either ignored them, or embraced them. That was one of their better decisions. 
"That is a brief overview of our history. About a thousand years ago, during the Middle Ages, or the Dark Ages, two wizards and two witches, Goderic Gryffindor, Salasar Slytherin, Helga Hufflepuff and Rowena Ravenclaw, founded Hogwarts, a school for young witches and wizards. Most witches and wizards here in the UK have been to Hogwarts. But it is your own choice. If you don't want to go to Hogwarts, you don't have to."
"But I want to."
Her mother smiled. "I thought you'd say that.  We'll visit Diagon Alley tomorrow, to get your school supplies." 
"Diagon Alley?"
"A cobbled wizarding alley and shopping area. There was a supply list with your letter, wasn't there?"
"Yes, there was, but –"
"Then we'll get your stuff tomorrow. Go to bed, Storm, tomorrow will be a long day."
"Okay." Storm rose and walked to her room, but she did not go to bed. She climbed out of the window and onto the roof, where she looked at the moon and the stars. She always looked at the moon and the stars if she needed to think. That or running. Her mother knew that Storm would be on the roof, but Minerva decided to let Storm stay up. Storm would go to bed on her own. Professor McGonagall sighed, got up and wrote two letters. First a short one,  in which she announced that Storm McGonagall would be attending Hogwarts in the fall. The second one was harder. It was a personal letter, which took ten tries to write. She left the drafts on her desk and gave the letters to her owl – "To Albus, Chris." She went to bed, after telling Storm that she had to go to bed too.