A letter from the mother of a young cancer sufferer to author Jk Rowling has been read out during a performance of the Letters Live series in London. Actresses Carey Mulligan and Ellie Bamber read out the emotional letter from Chrissy Hart, who said Rowling’s Harry Potter books had helped her daughter through her cancer treatment.

JK RowlingA mother’s letter to JK Rowling was read out as part of the Letter’s Live series this week.

“I write to you as a mother, a Mummy, of a beautiful little girl. I'm sure you hear people tell you all the time that your words, your imagination helped them, or their children, in some way,” Ms Hart wrote.

Ms Hart went on to describe how reading Rowling’s novels to her daughter helped her get through her cancer diagnosis and chemo treatment.

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"I want to share with you what you taught my daughter, who was recently diagnosed with cancer. When I read her your stories, she didn't take to the clear distinction between good and evil, but instead loved the grey characters."

“You taught her that for every chemo she has to go through, there will be the opportunity to fly across a lake on a hippogriff. For every time her heart seizes with fear of pain, there will be me chasing it away with a patronus charm.”

"Your words built a castle for her to move into when the prognosis got worse. Mrs Rowling, cancer threatened to take everything from my daughter, and your books turned out to be the fortress we so desperately needed to hide in.”

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Ms Hart said the books had also taught her about courage, love and protection given them both, “Hogwarts as a home for her to return to. And for me.” At the event organisers sadly confirmed that Ms Hart’s daughter had died earlier that week.

The Letters Live series, which is being held at Freemason’s Hall in London, features remarkable letters read out by famous names. Benedict Cumberbatch and Olivia Colman are also due to perform later in the series.