
Ever since the 
announcement that 
Carter Burwell (
Twilight's score composer) would be returning to 
The Twilight Saga: Breaking Dawn, 
Twilight fans have been wondering whether that means 
Robert Pattinson ("Edward Cullen") would be playing "Bella's Lullaby" once again in the film (as is done in the book).
 According to a post on Carter Burwell's homepage, the answer is yes.
And he just wrote "Renesmee's Lullaby" for Twilight Breaking Dawn 2,  which Rob Pattinson will play on camera. The film will be released in  November 2012.
The same was done in Twilight, and it was a huge success.
 Aside from Burwell, composers on the Twilight series scores have been Alexandre Desplat (The Twilight Saga: New Moon) and Howard Shore (The Twilight Saga: Eclipse).
 In Twilight, Robert Pattinson actually did play the  keys for Carter Burwell's "Bella's Lullaby," but the film used  Burwell's recording over it. From the language of Burwell's post, it  seems the same will be done for Breaking Dawn - Part 2 (release date November 2012).
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