Cecelia Ahern - Author of 'P.S. I Love You', talks about her new book 'Roar', where she writes and what it's like to have sold 25 million books.

Writer's Routine - Cecelia Ahern - Author of 'P.S. I Love You', talks about her new book 'Roar', where she writes and what it's like to have sold 25 million books.