He is one of the most iconic and loved characters in the best selling series of books.
But now JK Rowling has revealed her own son was left devastated after discovering she had killed off Professor Dumbledore in the Harry Potter books.
The writer, 60, said she discovered him in bed reading The Half Blood Prince.
But he asked ‘why did you kill Dumbledore?’ when she went to wish him goodnight.
The story emerged after Rowling responded to a comment on social media site X, formerly Twitter, from a woman whose daughter had read the book.
US-based Christine Harrington said: ‘My sixth grade daughter is reading Harry Potter, she finished the sixth book very late the other night so I was already asleep.
JK Rowling has revealed her son was left devastated when he read Professor Dumbledore had been killed off after reading The Half Blood Prince
Michael Gambon portrayed the much-loved character in the 2005 film Harry Potter and the Goblet of Fire
‘I awoke to a post it on the kitchen counter, “Mom, Dumbledore died! I’m so sad”.
‘This small note made my heart explode. Reading great books is magical and moving and heartbreaking.
‘Thanks @jk-rowling for writing this world for kids to love and live in.
‘Parents, too many kids today haven’t read all the Harry Potter books. Start reading this series with them. I promise it will be one of your most cherished memories.’
Rowling, who has two daughters and a son, replied: ‘That’s such a lovely message and reminds me of the night I went to say goodnight to my nine-year-old son, who I found with Half Blood Prince face down on his duvet, and who said to me solemnly, “Why did you kill Dumbledore?”.’
Ms Harrington was left stunned by the reply and posted: ‘Wow! Thank you so much for this heartfelt message.
‘My daughter is in shock that THE JK ROWLING replied!!! You’ve truly just given her a lifetime memory.
‘I hope she reads your novels to her children someday and when they reach the end of book six she shares this story and shows her children your reply! And then she can give them my advice: keep reading, it turns out to be a happy ending...I promise.’
Dumbledore was killed by Professor Snape in the sixth book in the series.
It is later revealed that the death was pre-planned and the Hogwarts headmaster was already dying.