Fey: I gave Shepard hair insult

Adam Driver, Corey Stoll, Tina Fey and Jason Bateman star in This Is Where I Leave You (Warner Bros)

Tina Fey has revealed that a joke about older women having centre partings in her new film was her idea.

The funnywoman, who stars in family drama This Is Where I Leave You, offered the line to co-star Dax Shepard, before she punches him for a scene.

"When you do a fake punch in the movie, the person who makes it look good or not good is the victim. So Dax... he really sold it," she said.

"In exchange for that, I did give him one line when we were shooting that scene. During that scene, Dax was trying different things to insult me and I said to him, 'If you really want to insult me, you should say I'm too old to have a centre parting in my hair', which he enjoyed very much."

Tina, 44, said of the hairstyle: "I just think it becomes questionable for a woman my age. It's not as bad as pigtails, that would be out of the question."

Meanwhile, Jason Bateman has revealed the film's cast, including Adam Driver, Rose Byrne and Jane Fonda, bonded like a real family because they shot in a real house.

"We all share snacks and stories, play Words With Friends, help each other with our lines, and take turns going to the bathroom," he said.

"My family wasn't as bickerish as this family. But I did have a lot of fun with my sister growing up and I tapped into that, playing with this one," he continued, pointing at Tina. "We had a really fun time on the set making our lines feel alive and authentic and she made that very easy."

This Is Where I Leave You opens in cinemas on October 24.