Kate Winslet has said she was "blown away" by her daughter's courage when they acted opposite each other for the first time.
The actor shares the screen with 21-year-old Mia in family drama I Am Ruth, a feature-length instalment of female-led drama anthology series I Am, which was created by filmmaker Dominic Savage.
The film follows a worried mother whose daughter starts to retreat into herself as she becomes consumed by the pressures of social media.
Appearing on ITV's Lorraine, Winslet said some actors had been discussed for the part of the teenaged daughter when Savage mentioned Mia, her daughter with her ex Jim Threapleton.
“He said, ‘What about Mia?’ and I said, ‘You have to audition her and that has to be separate to me’, and it worked out," she said.
“As far as performance, she didn't need me at all. There are even moments where she’d look at me and go, ‘Shut up Mum, let me do it!’"
Winslet, 47, told host Lorraine Kelly: "It was really amazing working alongside her and actually being blown away by her courage… she's very, very powerful.”
The star also shared that Savage liked the cast to improvise.
"There are no scripted words written, it's terrifying," she said.
"You make it up as you go along, so it was really challenging and quite an exhausting and demanding process. What you get to see is people really laid bare and a lot of vulnerability.”
Winslet, also mum to sons Joe and Bear, said the subject matter resonated with both her and Savage, who is also a parent.
"This idea of mental health and how hard people are finding it to raise children in the current climate," she said.
“Teenagers with social media and this sort of addiction to phones, and then getting sucked into a completely unknowable world. And it separates them at times from families and becomes very, very hard to be not only a parent but particularly hard to be a mother.”
The star went on: “Covid has not really helped young people. I think particularly that young generation all the way up to 16, 17 - they were missing experiences at school, social interactions, that basic thing of walking into a room and introducing themselves to a stranger for the first time. These are simply things that they haven't experienced yet and missed out on.
“They feel angry about it, they feel cheated, they feel frustrated about the systems that were put in place that prevented them from being able to see their friends. And they feel that something has absolutely been taken from them.”
I Am Ruth airs on Channel 4 this December.
Watch: Kate Winslet has motherly 'instinct' while working with daughter Mia