Nicole Kidman's contentment in her family life makes her able to "tackle everything"

She said: "It makes you able to go out and tackle everything."

When she was growing up, the 49-year-old actress - who also has Isabella, 24, and Connor, 22, with her ex-husband Tom Cruise - spent time with her mother Janelle, a nursing ex ecutive, which she says informed her role in 'The Killing of a Sacred Deer'.

She told the Daily Mail newspaper: "All through my childhood I'd go to the hospital with my mum. In 'Sacred Deer', they said, 'Oh, we need to teach you how to apply a tube to a patient,' and I said, 'I know how to do that!' I wasn't boasting. I had watched Mum do it for years ... It's only pretend in the movies. Mum did it all for real."

Meanwhile, Nicole previously revealed she approaches her acting career like she's 21-years-old again.

She explained: "I’m at that place in my life where I try to act as though I’m 21 and starting my career.

"At this stage in my life, I’m trying to stay bold and open and try things and support filmmakers that I believe in."

And the blonde beauty confessed to turning down work for the sake of her family.

She added: "My time is precious, I think once you reach a certain age the time becomes incredibly important - you're like [gasp]. I'm raising a six and an eight year old who are in school so there's only a certain amount of time I can work because of their school year.

"That means I pass on things a lot ... because ultimately - and this is just me - my family life is the most important thing to me so I'm not going to jeopardise that in any way shape or form."