Sofia Coppola thinks having children has changed her approach to filmmaking.

The 49-year-old director - who has Romy, 13, and Cosima, 10, with husband Thomas Mars - has admitted she now has less time to sit around and ''daydream'' about movie projects.

She shared: ''There's a moment when you have little kids and you're working and thinking, 'Who are you?'

''You get lost in the shuffle, and then you find your way. I don't feel like that now, but there was a moment I had to figure it out. As a writer I used to stay up all night, but when you have kids you can't.

''As a writer you need hours to daydream. Then, suddenly, it's 'babysitter for two hours - be creative!' It was a whole different shift.''

Sofia's new film, 'On the Rocks', is a ''father and daughter buddy story''.

And the acclaimed filmmaker has admitted the movie was partially inspired by her own father, legendary director Francis Ford Coppola.

Sofia - who previously helmed the award-winning 'Lost in Translation' - told the Sunday Times newspaper: ''I have so many memories and quotes from my dad, and that relationship was really impactful on me.

''Felix is made up, yet there are elements of my dad. He was bigger than life to me growing up. But Felix is this international playboy, so he's a combination of my dad and my dad's friends.

''Also, my father-in-law is a fun big character. It is a bunch of figures in my life from that generation.''