Vernon Dursley gets a letter from Hogwarts. Story starts two days after the end of "Return to Privet Drive."
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Harry and his daughter Lily arrived at 4 Privet Drive, Dudley had the door open before they could knock. "Come in Harry, thanks for coming so quickly."
Patricia Dursley made some tea whilst young Vernon Dudley Dursley showed his cousins the mysterious letter.
Dudley said "Is this a joke or for real, how can a train leave from Platform 9 3/4?"
Harry said "You know its real Dudley, that is where I would disappear to at the end of every summer as a teenager. Young Vernon must have inherited some magical ability from his Great Aunt Lily, my mother. This is where I went to school Vernon, your latent magic must have been detected and your have got the letter from the great magical school Hogwarts."
Vernon said "What is this school like?"
Harry said "my wife and our three children all went to Hogwarts. Unfortunately Ginny is reporting on the England Bulgaria Quidditch match today, James and Albus are both working. However Lily only left two years ago, now she works as a trainee Healer at St. Mungos. Lily is a smart young lady, just like her Aunt Hermione, she was head girl. OK Lily, tell your cousin about Hogwarts..."