Harry Potter fans are today marking the 18th anniversary of the Battle of Hogwarts, which took place on May 2nd 1998. To mark the anniversary, author Jk Rowling has apologised to readers on Twitter, for the death of much-loved character Remus Lupin, who was killed by a Death Eater during the battle.

JK RowlingJK Rowling has apologised for the death of Remus Lupin.

‘Once again, it's the anniversary of the Battle of Hogwarts so, as promised, I shall apologise for a death. This year: Remus Lupin,’ Rowling tweeted. ‘In the interest of total honesty I'd also like to confess that I didn't decide to kill Lupin until I wrote Order if the Phoenix.’

‘Arthur lived, so Lupin had to die. I'm sorry. I didn't enjoy doing it. The only time my editor ever saw me cry was over the fate of Teddy.’ Rowling then retweeted a fan who had written ‘Remus is and always will be my favourite character in the Harry Potter universe,’ with the author calling it ‘The best tribute he could have.’

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The Battle of Hogwarts takes place in the final Harry Potter novel, The Deathly Hallows and featured a number of high-profile casualties. Lupin was killed by Death Eater Antonin Dolohov and his wife Nymphadora Tonks was killed by Bellatrix Lestrange, leaving their son Teddy an orphan.

The battle also saw the end of Severus Snape, Fred Weasley and Lord Voldemort. Back in 2007, Rowling admitted that she hadn't originally intended to kill Lupin, instead if was meant to be Arthur Weasley.

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“If there's one character I couldn't bear to part with, it's Arthur Weasley,” Rowling said. The author then added that she had wanted to kill a set of parents in the final book, to echo what had happened to Harry.

“I think one of the most devastating things about war is the children left behind,” Rowling said. “As happened in the first war when Harry's left behind, I wanted us to see another child left behind. And it made it very poignant that it was (Teddy) their newborn son."