I first started reading Harry Potter from the 3rd book, fell in love with it and brought the first 2 and went on to get the set. Since then I've been an avid reader of the books and viewer of the films.
What a great start to your story. You have me gripped from the beginning. Must move onto chapter two and find out what happened to the rest of the family.
Wow, I have a funny feeling that Dieter is a Muggleborn Wizard (since his brother couldn't see the house). This story is going to be very interesting.