In her latest thriller, Bird Box, Sandra Bullock plays a mother of two young children -- a role that mirrors the actress' real-life role as a mom to an 8-year-old son and a 6-year-old daughter.
While she spends most of the movie's running-time trying to protect herself from an unseen evil, Bullock says the atmosphere on set was a lot lighter, as she was able to bring her kids, Louis and Laila, to the shoot, where they got a chance to hang out and play with the young stars of the film.
The 54-year-old actress, who stunned in a red criss-cross halter gown by Martin Grant, spoke with ET at the premiere of Bird Box at Alice Tully Hall at Lincoln Center in New York City on Monday, and she opened up about her kids' time with her child co-stars, Vivien Lyra Blair and Julian Edwards.
"LEGOs was a big thing, [also] tag and catch," Bullock recalled. "I mean, when you get to little people, there are basically three things that they like to do, and all three of those were done on set."
Bullock added that she feels really lucky to work in an industry that gives her the chance to have her kids so close while working.
"How many people would love to be able to take their children to work and have that embraced?" Bullock asked. "It's so accepted and I feel like every set that I work on has sort of a familiar aspect to it [and] a safe feeling for family members."
Feeling safe is a luxury that Bullock's character in Bird Box doesn't get a chance to enjoy. The film -- which tells the post-apocalyptic story of a world under attack by creatures that can kill you just by looking at them -- deals a lot with the nature of fear and its impact on your life.
One of the fears Bullock's character faces in the tense thriller is the decision and consequences of being a mother, and bringing new life into a challenging world.
However, in the actress' real life, Bullock says she never felt any fear of motherhood, and actually embraced the prospect early on.
"I would have been pregnant or knocked up at 17," the Oscar winner shared. "I wanted to be a mom at a very young age. So I kind of felt the drive and the desire to."
Bullock added that there's one main reason why that didn't happen.
"My mother knew that and she kept me under lock and key," the actress explained.
Bullock became a mom for the first time in 2010 when she adopted son Louis, and welcomed daughter Laila into her life via adoption in 2015.
Recently, ET sat down with Bullock and her Bird Box co-star, Trevante Rhodes, and the actress revealed how her time as a mom helped to inform her role, especially when it came to becoming a fierce protector of her children, on-screen, against the film's menacing danger. Check out the video below to hear more.