“It’s a very family-style set,” Sienna Miller said of filming “Horizon: An American Saga” during an appearance on “The Jess Cagle Show with Julia Cunningham” with co-star Sam Worthington.

The Jess Cagle ShowSienna Miller & Sam WorthingtonListen on the AppListen on the App

Sienna continued, “I have a beautiful picture of my eldest daughter, Marlowe, standing next to Kevin [Costner] by the monitor, sharing headphones from behind, watching a scene, and he had her dressed up in clothes … if she wanted to be in a scene.”

When asked if 11-year-old Marlowe decided to make a guest appearance on “Horizon,” Sienna said her daughter “chickened out of actually being in a scene” but “might have caught the director bug” from Kevin.

“I’m gonna nudge her towards directing, so I always have a job,” Sienna joked.

Marlowe enjoys using an eight-millimeter app on Sienna’s phone to film and edit dinner party scenes in a way Sienna described as “actually pretty impressive” and “quite Scorsese-esque.”

Listen to Sienna and Sam’s full interview on SiriusXM.

“The Jess Cagle Show with Julia Cunningham” airs Monday through Friday at 2pm ET on Radio Andy (Ch. 102) with full episodes available to stream anytime on the SiriusXM app.