Keira Knightley knows that the balance of work and parenthood can be a challenging one — especially when you have to step into a completely different character.
The actress, 34, recently chatted with the New York Post‘s Page Six about her new role as real-life intelligence translator Katharine Gun in the upcoming political thriller Official Secrets, revealing that filming while getting her now-4-year-old daughter Edie into a new bedtime routine wasn’t exactly the ideal combination.
“Any actresses out there, do not move the child from the [crib] to the bed when you’re just about to play a lead role in a film that has a lot of words in it because remembering them is quite tricky,” she joked.
The soon-to-be mother of two admitted to the outlet that she “felt very on edge, but for different reasons” during production — so she “used it all,” Knightley said.
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The pregnant star doesn’t talk about her daughter very often, but opened up in a March interview on Live with Kelly and Ryan about Edie’s favorite show at the time.
It’s the theme song that the former Pirates of the Caribbean and Love Actually star can’t stand — but as with many children, the show always seems to suck her daughter in.
“It’s like The Matrix, like you plug her in and she’s just there,” Knightley quipped. “But it’s so annoying, the theme tune, and it’s only about seven minutes or something so the theme tune happens a lot.”
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News of Knightley and husband James Righton‘s second child on the way came in early May, when the actress stepped out in Paris wearing a cream-colored, sheer gown that clearly showed off her growing baby bump.
The star was beaming as she held hands with Righton, 35, as they walked into the Place Vendôme outing, and was later spotted sweetly cradling her belly.
Knightley has yet to publicly talk about the pregnancy, and her rep did not immediately respond to PEOPLE’s request for comment at the time.
Official Secrets hits theaters on Aug. 30.