Goodbye Christopher Robin exclusive featurette looks at the real-life inspiration behind a literary classic

We all know the Christopher Robin who populates the pages of A.A. Milne's book, the friend to many creatures of the Hundred-Acre Wood.

But what of the real Christopher Robin? More precisely, Christopher Robin Milne, or as his family would often call him, Billy Moon. As a boy, Christopher Robin was gifted a teddy bear he named Edward; this toy, alongside a real Canadian bear named Winnipeg Milne saw at the London Zoo, became the inspiration for Winnie-the-Pooh.

However, Christopher Robin's life wasn't entirely a literary dream, as new film Goodbye Christopher Robin hopes to explore: a child who became consumed by the spotlight, and later sought to flee it in any way he could.

Directed by Simon Curtis, the film stars Domhnall Gleeson as A.A. Milne and Margot Robbie as his wife Daphne de Sélincourt, with the adorable Will Tilston filling in as a young Christopher Robin.

A new featurette explores the casting process for the film, and how they managed to land their young lead; the cast also features the likes of Kelly Macdonald and Fleabag star Phoebe Waller-Bridge.

Goodbye Christopher Robin is out in UK cinemas September 29.