Brad Pitt says the making of his latest film Fury made him a better father to the six children he has with Angelina Jolie.
He told Sky News it was a life-changing experience.
"The film focuses on leadership, and when you build someone up and when you need to take them down a notch, and it was this kind of focus which speaks to fatherhood," he said.
The actor was speaking at the premiere of the Second World War film, which closed the London Film Festival.
Fury sees him play a tank commander during the war. The film has been described as the most realistic war movie ever made.
Pitt said it made him appreciate what soldiers do and gave him a better sense of what they went through on the battlefield.
"I understand much better what they endure, the psychological trauma they endure, what they went through mentally and physically," he said.
He also told Sky News he was proud of his wife, who was recently awarded an honorary Damehood by the Queen.
"It was one for the books," he said.