Anne Hathaway insists she's usually a "very, very bad liar" -- except when it came to her pregnancy.
"I get very flushed when I lie, so I am very bad at keeping secrets. People can always tell what's up," the 33-year-old actress tells ET's Cameron Mathison at the Toronto International Film Festival while promoting Colossal. "The only secret that I kept, and I will tell you I got really good at lying, was when I was pregnant."
She adds, "I lied about everything having to do with it."
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Hathaway explains that she chose to be untruthful about her pregnancy as a way of shielding her child-to-be. "I did not feel like, 'Oh, I am lying,'" she confides. "It was like, 'No, I am protecting.'"
She quips, "I am a boxing-out mama bear."
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Hathaway and husband Adam Shulman welcomed their baby boy, Jonathan Rosebanks, in March. A few months later, she spoke to ET about shedding her pregnancy weight and how Shulman was doing with fatherhood. Check it out:
Colossal, in which Hathaway plays an alcoholic writer who discovers she has a psychic connection with a monster destroying Seoul, South Korea, is slated to hit theaters in 2017.