I'm just gonna take this opportunity to list off a few incredible opening lines that are way better than anything JKR has ever written.
All this happened, more or less.
Kurt Vonnegut Jr., Slaughterhouse Five
One morning, when Gregor Samsa woke from troubled dreams, he found himself transformed in his bed into a horrible vermin
Franz Kafka, The Metamorphosis, Trans. David Wyllie
No live organism can continue for long to exist sanely under conditions of absolute reality; even larks and katydids are supposed, by some, to dream.
Shirley Jackson, The Haunting of Hill House
This is not for you.
Mark Z. Danielewski, House of Leaves