If there's one thing that author JK Rowling truly regrets, it's not telling her dying mum about the book idea for the Harry Potter series that has made her a household name across the world.

Rowling, who started writing the first Potter book - the Sorcerer's Stone - six months before her mother died, had promised herself that she would never reveal to anyone that she was writing a book about a boy wizard.

However, that's one decision that she now regrets.

"That's one of my biggest regrets; she never knew, I never told her," Contactmusic quoted her, as saying.

Rowling adds that her mother's death had a 'profound influence' on the way she was writing, especially the subject of death.

"Mum dying had a profound influence on the books because in the first draft his (Potter) parents were disposed of in quite an almost cavalier fashion. I didn't really dwell on it. Six months in, my mother dies and I simply can't kill a fictional mother that callously... It wasn't what it became," she added.

The Harry Potter series came to an end recently when the final book - The Deathly Hallows - was released worldwide on July 21. (ANI)