'Happiness can be found even in the darkest times': J.K. Rowling's heartfelt letter to teenage survivor of gun massacre who quoted Harry Potter film at memorial for her family

• Author sent handwritten letter in purple ink from her character Dumbledore to Texas girl
• 15-year-old had pretended to be dead after a gunman killed her parents and four siblings last month
• Facebook support page campaigned for Rowling to contact Cassidy Stay

By Press Association and Jessica Jerreat

Published: 19:34 EDT, 6 August 2014 | Updated: 05:37 EDT, 7 August 2014

Harry Potter author J.K. Rowling has written a heartfelt letter to Cassidy Stay, who survived a gun attack that killed her parents and four siblings in Texas last month.

The 15-year-old, who had played dead after a gunman attacked her family, had quoted part of a speech given by Hogwarts headmaster Albus Dumbledore in the third film of the popular series.

Bravely speaking at a memorial just days after the July 9 attack, Cassidy had quoted the film, saying: 'Happiness can be found even in the darkest times, if one only remembers to turn on the light.'

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Strength: Cassidy Stay, 15, quotes a line from the Harry Potter films during a memorial for her family

Comfort: Harry Potter author JK Rowling sent a handwritten letter to Cassidy Stay after hearing how the teenager had quoted Dumbledore at a memorial for her family

An online campaign to get J.K. Rowling to contact the teenager led to the world-famous author writing to Cassidy in the voice of Dumbledore, The Daily Telegraph reported.

The handwritten note of comfort, written in purple ink, was accompanied by a wand, an acceptance letter to Harry Potter's school Hogwarts, a list of school supplies and a signed book.

A spokesman for the 49-year-old author told the newspaper: 'We can confirm that J.K. Rowling was in touch with Cassidy Stay, however, the contents of the letter remain private.'

Asked whether a meeting between the two may happen, she added: 'We wouldn't comment on that but [Cassidy's] is a remarkable story.'

After quoting from the film The Prisoner Of Azkaban, Cassidy said: 'I know that my mom, dad, Bryan, Emily, Becca, and Zach are in a much better place and that I'll be able to see them again one day. Stay strong.' 

Support: Cassidy with a Harry Potter themed cake donated to her by the Bareback Bar and Ice House, which held a fundraiser in memory of her family

Inspiration: In her speech at the memorial Cassidy quoted part of Dumbledore's speech at the start of the third Harry Potter film

The line was spoken in the film by Harry Potter's mentor Dumbledore - played by Sir Michael Gambon - when he addressed students at the start of the film.

The quote was credited to writer Steve Kloves, who transformed all seven books into screenplays.

After the service, the We Want J.K. Rowling to Meet Cassidy Stay Facebook page was set up in support of the teenager.

On Monday, a post appeared on the page, which by Wednesday had attracted more than 6,500 likes, confirming that the author had contacted the teenager.

'This afternoon, I talked to a friend of Cassidy's who confirmed that J.K. Rowling did, in fact, write her a personalized letter from 'Dumbledore' (hand-written with purple ink),' the post read.

'I'm so excited and ecstatic that we were all able to make a difference! How wonderful. However, I still really want J.K. Rowling to actually meet her.'

Since the gun attack on her family, Cassidy has had far-reaching support, with well-wishers donating more than $390,000 to help the teenager through a Go Fund Me site.

Survivor: Cassidy Stay at her family's memorial on July 16. The teenager helped save her grandparents by playing dead and then calling police to tell them of the gunman's plans 

Businesses in her Texas community have also shown their support by holding fundraisers for Cassidy.

The Bareback Bar and Icehouse in Spring, Texas, held a Stay Family Benefit, and also donated a Harry Potter themed cake to Cassidy, that was baked to raise more funds, KVUE reported.

The 15-year-old, who played dead after a gunman forced her and her family to lie on the floor while he shot them, was credited for saving the lives of her grandparents and other relatives, by calling police after the attacker left.

Katie Stay, 34, Stephen, 39, and their children Bryan, 14, Emily, nine, Becca, seven, and Zach, four, died in the attack.

Ronald Haskell, 33, has been charged with murder.