The 80-year-old actress originated the role on film in 1964.
Emily Blunt may be nervous about stepping into the big boots of Mary Poppins in an upcoming remake, but she's already won over one important person -- Julie Andrews!
While the 33-year-old actress hasn't spoken to Andrews herself, Blunt told Entertainment Weekly that her Mary Poppins Returns director, Rob Marshall, spilled the beans on her casting when he ran into the Academy Award-winning actress recently.
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"Rob said he was in the Hamptons and he saw [Andrews], and he said 'It's top secret but Emily Blunt's playing Mary Poppins,'" she recalls. "And she went, 'Oh, wonderful!'"
Andrews, now 80, originated the role of the beloved spoonful of sugar-pushing nanny on film in 1964, and won a Best Actress Oscar for her performance -- so we can see why her blessing would be important.
"I felt like I wanted to cry," Blunt admits. "It was lovely to get her stamp of approval. That took the edge off it, for sure."
The Into the Woods actress also admits she still feels some trepidation at taking on the iconic role. "[Mary Poppins is] so emblematic of people's nostalgia," Blunt says. "It's such an important character in people's childhood."
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The film is currently slated for a December 2018 release and will also star Hamilton's Lin-Manuel Miranda.
ET caught up with Blunt’s husband, John Krasinski, earlier this month, where he dished on his wife's singing voice and Poppins prep. Check out this video for more.