Nicole Kidman would "absolutely" support her adopted children if they wanted to find their biological family.
The 49-year-old actress is mother to Isabella, 23, and Connor, 21, who she adopted along with ex-husband Tom Cruise when they were married.
Now exploring adoption in her new movie Lion, the subject has frequently come up for Nicole as she promotes the film, and in a recent interview with E! News, she was asked what she thinks about adopted children searching for their birth parents.
"That's part of my belief on adoption," she said. "Yeah, of course - if a child wants to find their birth mother, I'm absolutely supportive of that."
Lion tells the story of a couple which adopts a young Indian boy who loses his parents after getting lost on a train. Nicole plays Saroo's adoptive mother Sue Brierley. As he grows older, Saroo, played by Dev Patel, is desperate to find his long-lost family, and searches for them online using Google Earth.
Nicole also has two biological daughters, Faith and Sunday, with musician husband Keith Urban. While both Nicole and Keith will celebrate their 50th birthdays next year (17), the actress in June and her singer spouse in October, the redheaded beauty admits she hasn't started thinking about what to do to mark the occasion.
"As I said, everyone keeps jumping a year ahead. We're jumping a week ahead," she smiled. "That's all we can do in our lives right now."
Instead, her main focus is preparing for Faith's sixth birthday this December.
Asked if they were planning a joint party for their birthdays, Nicole replied: "We'll see. (Right now) we're thinking about Fifi's birthday. She's the next birthday on our list."
Lion is based on true events and premiered at the Toronto International Film Festival in September (16). It's director Garth Davis' big screen debut, and hits cinemas from 24 November (16).