Lena Dunham cast her dog Ingrid in 'Catherine Called Birdy'.

The 36-year-old 'Girls' creator wrote and directed the 2022 medieval comedy film - based on the 1994 novel of the same name by Karen Cushman - and Dunham joked that she "believed in" Ingrid when she cast her as the baby Jesus in the Christmas pageant scene.

She told The Hollywood Reporter: "Ingrid was with me through writing, scouting and shooting this movie. As we were traveling to these medieval buildings, we would see these old paintings of saints and peasants with their dogs. They all looked a little like Ingrid — she has a very medieval look.

"I gave her the role. People were sceptical, but I believed in her!"

Lena also collaborated with her husband, musician Luis Felber, on the film’s soundtrack.

And Lena revealed the novel's original cover art inspired her to cast Bella Ramsey, 19, in the title role of Catherine aka Birdy.

She said: "That was the face of Birdy I always saw. When I saw Bella’s face, it summoned so many of those same qualities that the character has — very classical beauty coupled with intelligence, [and] wide-eyed innocence coupled with trickery."

'Catherine Called Birdy' features a star-studded ensemble cast including Andrew Scott, Billie Piper, Joe Alwyn, Russell Brand, Sophie Okonedo and Lesley Sharp.