When Netflix released "Bird Box" — starring Sandra Bullock — in December, the horror movie set a new record for the streaming giant, becoming the most-watched film within the first seven days of its release. Now, the 54-year-old actress is revealing the sweet reason why she signed on to do the flick.

While accepting the 2019 MTV Movie & TV Award for most frightened performance, Bullock told the audience that she credits her two little ones — daughter Laila, 7, and son Louis, 9 — as to why she did the movie.

"I made 'Bird Box' because my children asked me why I never made anything for them," Bullock shared. "So when 'Bird Box' crossed my path, I knew this was a story I needed to make because it was about family."

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"And when I finished the film, I went to my babies and I said, 'Here, mommy made this for you. And even though you can't see it until you're 21 — because apparently, a movie about being a mommy is a horror film — you will know when you see it that there isn't anything that I wouldn't do for you," she continued.

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Added Bullock: "I wanted you to see what being family looks like — that sometimes you're born into a family, sometimes you need to go find it, sometimes it finds you — but no matter how it comes together, that when it does, family is what you fight for, family is what you protect, and what you saw in that movie is what your mommy would do for you."

The mom of two went on to say that she told her kids that they are her "first thought in the morning" and her "last thought at night."

"I was put on this earth to protect you. You are my world. I love you so much," she gushed. "I will move mountains to make sure that you are safe."

Sandra Bullock accepts the award for most frightened performance for "Bird Box" as presenter Gal Gadox looks on at the MTV Movie and TV Awards at the Barker Hangar in Santa Monica, Calif. (Chris Pizzello/Invision/AP)

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"And when I was finished, my son looked at me with his big, beautiful eyes and he said, 'Mommy, it was superhero movies I was talking about. Those are the films you should be making. Superheroes are the ones doing the important work right now,'" Bullock hilariously revealed about her son's reaction before teasing: "I grounded him."

Bullock concluded her speech by saying that she was happy her son could see her accept her award in a room with "real life superheroes" like Wonder Woman — played by Gal Gadot who presented Bullock with her Golden Popcorn trophy — and Captain Marvel — played by Brie Larson who won the best fight award.

"I'm sure he will notice that they are women, just like his mama," she said.

One week after its December 21 debut, “Bird Box” was viewed by over 45 million accounts, making it Netflix’s most-watched film within the first seven days of its release, according to the streaming giant. The movie also flooded social media with dozens of memes and inspired a viral social media challenge.

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At the time, Netflix went on Twitter to announce the news about "Bird Box's" success.

"Took off my blindfold this morning to discover that 45,037,125 Netflix accounts have already watched 'Bird Box' — best first 7 days ever for a Netflix film!" the company wrote alongside a GIF of Bullock, who stars as Malorie in the movie.

The Associated Press contributed to this report.