But she added that not everyone likes her work. Christian groups have alleged the books promote witchcraft. The author said her revelation about Dumbledore would give them one more reason.
The seventh Potter book broke sales records on both sides of the Atlantic when it was published in July, selling 11 million copies in 24 hours.
The fifth film adaptation of the series, Harry Potter and the Order of the Phoenix was released this summer. Harry Potter and the Half-Blood Prince is due for release late next year.