"..there's at least one death that's going to be horrible to write," she said in a BBC interview.
On board the Hogwarts Express
We can also expect more romance in books five, six and seven as the characters get older and get interested in the opposite sex.
But while Potter enthusiasts have the next three books to look forward to, an idea to let fans on board the Hogwarts Express has been turned down.
The train used in the Harry Potter film is kept in a shed in Carnforth Station, Lancashire, and staff there wanted to turn it into a tourist attraction.
But they claim Warner Brothers, who made the movie, refused to give permission and said they would sue if they went ahead. Warner Brothers has made no comment.