After completing a degree in Journalism and Media Communications, Cecelia wrote her first novel at 21 years old. Her debut novel, PS I Love You was published in January 2004, and was followed by Where Rainbows End (aka Love, Rosie) in November 2004. Both novels were adapted to films; PS I Love You starred Hilary Swank and Gerard Butler, and Love, Rosie starred Lily Collins and Sam Claflin.

Cecelia has published a novel every year since then and to date has published 18 novels; PS I Love You, Where Rainbows End, If You Could See Me Now, A Place Called Here, Thanks for the Memories, The Gift, The Book of Tomorrow, The Time of My Life, One Hundred Names, How To Fall in Love, The Year I Met You, The Marble Collector, Flawed, Perfect, Lyrebird, ROAR, Postscript and Freckles.

To date, Cecelia’s books have sold 25 million copies internationally, are published in over 40 countries, in 30 languages.

Along with writing novels, Cecelia has created, produced and written original TV series including co-creating the US ABC Comedy Samantha Who?

Cecelia’s highly acclaimed collection of short stories, Roar is now in development for Apple TV+ with Nicole Kidman and Per Saari’s Blossom Films, Bruna Papandrea’s Made Up Stories and Theresa Park’s Per Capita Productions, along with Ahern’s own Greenlight Go Productions label. Cecelia has written a TV series currently in development with Picturestart, and a feature film sequel to PS I Love You titled Postscript with Alcon Entertainment is also in development.