'Mary Poppins Returns' greatest Easter eggs — including the key callback that unlocks the film's ending (SPOILERS!)

Warning: This story contains several major spoilers for Mary Poppins Returns.

One of the joys of watching Mary Poppins Returns is spotting the many callbacks to the original film. But not all of director Rob Marshall’s ideas made it in.

Speaking with Yahoo Entertainment, Marshall revealed why he cut out the S-word (that’s “supercalifragilisticexpialidocious,” obviously) and how a single line from the 1964 film determined the ending of the sequel, as well as the one Easter egg that even hardcore Poppins fans are unlikely to spot. Watch the interview above.

Speaking with Yahoo Entertainment, the director of Mary Poppins Returns (who also co-wrote and co-choreographed the film) recalled a scene in which Jack (Lin-Manuel Miranda) would have greeted Mary Poppins (Emily Blunt) with a familiar 14-syllable word.

“There is one that we never actually filmed or anything but we talked about: when Mary first lands, and she says, ‘How are you, Jack?’ and he says, ‘Supercalifragilisticexpialidocious,'” Marshall explained. (Watch above.)

Ultimately, he decided the line was too on-the-nose. “You have to be very careful with a film like this because you can abuse that sort of pulling from the first film,” he said. “You have to do it very strategically and carefully and feel like you’ve earned it.”

With that in mind, Marshall spoke fondly of the scene in which grown-up Michael Banks (Ben Wishaw) finds his St. Paul’s Cathedral snow globe — the one Julie Andrews held while singing “Feed the Birds” in the original Mary Poppins — in the attic. “It represents to me, in a way, the message of the film, about holding on to childlike wonder,” said Marshall.

He’s also quite proud of the film’s ending (once again, spoilers!) and explained to Yahoo Entertainment how little Michael’s tuppence from the original film, which wound up in the hands of Mr. Dawes Sr. instead of going to the pigeon-feeding woman, ended up accruing huge amounts of interest in the coffers of the Fidelity Fiduciary Bank.

As for that crazy Easter egg, it’s a piece of original furniture from the 1964 set — specifically, the table in the front hall of 17 Cherry Tree Lane. “It was at Club 33 at Disneyland,” said Marshall. “And I saw it there and I said to our production designer John Myhre, ‘That needs to be in our film.’ And it is.”

Mary Poppins Returns is in theaters.

Watch: Yes, Emily Blunt can sing ‘My Shot’ from Hamilton as Mary Poppins