It seems that Hogwarts will be one professor short with its last installment. According to MTV Movies Blog, actress Emma Thompson will not be returning for Harry Potter and the Deathly Hallows and instead will be making a sequel to Nanny McPhee.

"No, no, no," Thompson said when asked if she'll return to Hogwarts. "I'm making my own Nanny McPhee next year. They mean much more to me."

Thompson has appeared as Professor Sybil Trelawney in Harry Potter and the Prisoner of Azkaban and Harry Potter and the Order of the Phoenix, filming Nanny McPhee between the two films. She also added some details about the new Nanny McPhee film.

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"The working title is 'Nanny McPhee and The Big Bang'," she revealed. "It's not a sequel, actually, it's a new story." She also added, "[The second film] is set one hundred years later; the only thing that is the same is Nanny McPhee," she explained. "It's about two families: A family of country children, and a family of town children, [both] during the war. So it's about evacuees, and the father is away at war. So this time, the lone parent is the mother. That's what it's about: The big war, and a war between these two sets of extremely different children."

When asked to explain why she chose Nanny McPhee over Harry Potter and the Deathly Hallows, the writer/actress offered this.

"The Harry Potters are great big franchises that are something I'm not emotionally attached to or necessarily particularly creatively attached to," Thompson explained. "That's more like doing a turn, whereas the Nanny McPhees are something I've written. The art is in those films, they're very handmade, they're something that's very close to me. Those are the ones I really care about."