Locals of Dublin's seaside town Malahide may have been surprised last week to see their most famous resident author, Cecelia Ahern, perched on a rock on the beach writing a short story as the muse took her. Indeed, they may have had an even bigger surprise last night as she dressed up as Winnie the Pooh and went door-to-door with her husband David Keoghan and their two children, Robin (3) and Sonny (1).
In the warmth of her office, decorated in a feminine style with flowers, scented candles and upholstered wing chairs, we sit down to talk about her 10th novel, How To Fall In Love.
It's almost a decade since she published her debut novel PS I Love You and she has sold 16 million books to date. "That does sound amazing but the only way that happens is by me getting up and going to work 9 to 5 every day.
From the outside it sounds like you'll never have to work again but my every day is writing. I wrote PS I Love You for me because I was having issues and it helped me. Every single time I write I need to write from the same place. I need to write what moves me, what helps me, that's it."
She says her writing has become more to the point, more focused, since having her children. "I don't waste time. I don't float about the place and have a chat."
The idea for her new novel, How To Fall In Love, first came about four years ago after she watched the George Clooney film Up In The Air.
"I loved his character and that his everyday reality was bringing about other people's despair, travelling around and firing people. I thought, how could I do that with a character.
"That same week I came across a song called 'Talk Me Down', which is a Westlife song," she says with a smile (Westlife member Nicky Byrne is her brother-in-law). "When I heard 'Talk Me Down' I thought of a character whose job it is to talk people down but what if that person really isn't enjoying life and is trying to convince people that life is beautiful?"
The book deals with depression and she researched it carefully, reading up on the subject and getting a psychologist to vet the book. It's not the first time she has written about that point in a person's life where everything is going wrong.
"I think that's a theme in all of my novels where my characters have just lost a sense of themselves. When I wrote PS I Love You when I was 21, I was really sad. I call it my quarter-life crisis."
Do all of her books equally represent a particular time in her life? "They do. The Time Of My Life was the first book I wrote after having a baby and that was about someone who was confronted by their life for the first time. This one is about somebody helping someone else to see the beauty in life. I think my children do that for me and obviously my husband does too.
"He put a smile on my face and showed me how to enjoy life in a different way. I think children slow things down, they see the small things in life, that's what the book is about."
It's hard to imagine what is left for Cecelia to achieve. As well as the slew of bestselling novels, she has written the American television series Samantha Who, two original German TV shows, which are based on How To Fall In Love, the Hollywood film adaptation of PS I Love You and she has two more big-screen adaptations on the way with Love, Rosie and The Gift.
But it's somehow not surprising to find she is adding more strings to her bow. She has three children's books coming out next year and has been writing thriller and ghost stories too. Could one of these creepy stories become a novel? "There's a very strong possibility."
She has already written a ghostly novella due out next year, as well as a story for the Dr Who 50th anniversary e-book and she admits she has been writing children's stories since just after she had her daughter.
"I know the ones that Robin asks for over and over again are the ones. She has an amazing imagination."
The suggestion that she has finally moved out of the shadow of her father, Bertie Ahern, is an exasperating one. "I never felt like I was in the shadow of my dad. Maybe if I was in politics it would be difficult but I'm writing. It's like asking someone whose dad is a carpenter are you okay to be a hairdresser."
His retirement from public life has made some things easier however. "I have extremely inappropriate humour. That's why I'm not good at duty. Some people are still surprised by that. Maybe they think I'm some prissy, prudey little thing. People who know me know that I'm not." She pauses a beat before adding. "But I'm a very good girl!"
'How To Fall In Love' by Cecelia Ahern (published by Harper Collins)