The 35-year-old actress discussed 4-year-old Hazel and 2-year-old Violet while attending the film's Los Angeles premiere with her husband, actor John Krasinski, on Thursday.
"It's very special. Very unique experience," Blunt said of the Mary Poppins sequel while speaking to Entertainment Tonight.
"This is the first film that my daughter has seen, my older one has seen," she added. "My little one is probably too young. She's two, so she's like 'whatever.' But my older one saw it and loved it."
Blunt was all smiles in a white Yanina Couture gown with billowing sleeves as she walked the red carpet with Krasinski. Krasinski said on Wednesday's episode of The Ellen DeGeneres Show that he sobbed while watching Mary Poppins Returns.
"The first time I saw it, they give you a tissue box in the screening room," the actor told host Ellen DeGeneres. "They started screening the movie and 25 minutes into the movie, I stood up and went to the back of the room."
"I was pushing through all of the muffins and bagels that were in the back looking for napkins," he said. "I was crying so much I blew through the tissue box in 20 minutes, had to go to the napkins, and then when I ran out of napkins it was all sweater."
Blunt commented on Krasinski's reaction in an interview with ET the same day.
"I love that, when guys cry. I think it's a beautiful thing," she said.
Mary Poppins Returns opens in theaters Dec. 19. The movie is directed by Rob Marshall and co-stars Lin-Manuel Miranda, Ben Wishaw, Emily Mortimer, Julie Walters, Dick Van Dyke, Angela Lansbury, Colin Firth and Meryl Streep.
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Lin-Manuel Miranda, Dick Van Dyke attend 'Mary Poppins Returns' world premiere