Book date with JK for cancer care sister.
Olivia Ceraolo, 16, died from bone cancer nine months ago.
She was a huge fan of the Edinburgh-based writer's work which her 12-year-old sister, Julia, read to her to relieve her pain as she lay dying.
Two weeks before her death, Olivia received a letter from Rowling, who had heard of her illness through a friend.
Julia, from Pittsburgh, Pennsylvania, was picked out from 8000 Potter fans who entered an essay competition to attend the Edinburgh Castle launch of Harry Potter and the Half-Blood Prince on July 16.
Julia said: 'When Olivia was upset or in pain ... Harry Potter would make her laugh.
'JK Rowling brought joy to my sister and her books help me get through my grief.
'When I found out I'd been chosen to go to meet JK Rowling, I was jumping up and down, screaming my head off.'
On the private jet flight over with her mum Carla, Julia will be given the new book to read.
Rowling will read the book to an invited audience of children from across the globe - including Julia - at Edinburgh Castle