How Rita Wilson created a uniquely Greek celebration anthem for “My Big Fat Greek Wedding 3”

When it comes to the My Big Fat Greek Wedding franchise, everything is a family affair.

Rita Wilson has been part of the movie family since she produced the first film (and discovered Nia Vardalos via her one-woman show that became the inspiration for the original movie). But for My Big Fat Greek Wedding 3, Wilson not only serves as a producer, but she also wrote a song that plays a key role in the film's climax.

"Nia, knowing I'm a songwriter, asked if I would write a song for this movie," Wilson tells EW. The actress-producer-songwriter previously penned "Even More Mine" for the second film, but since this track was specifically a request from Vardalos, Wilson wanted to write something even more special — particularly because Vardalos fulfilled Wilson's request to make her directorial debut on the film (Wilson had wanted Vardalos to direct the second film, but Vardalos didn't feel ready).

"I had a very specific conversation with Nia about it," Wilson explains of recruiting Vardalos to direct. "I said to her, 'Well, you're going to direct this one, aren't you?' And she said, 'Am I?' And I said, 'Well, no one is telling you not to, and I'm telling you you are.' And she said, 'Okay, I'm directing it.' Everybody in our group wanted that. Who better to direct it than Nia, who's lived with it for 20-something years and knows the characters inside and out?"

Taylor Hill/FilmMagic; Courtesy of Focus Features Rita Wilson; Nia Vardalos in 'My Big Fat Greek Wedding 3'

As for the new director's request, Wilson co-wrote "Oli Mazi (We Are All Together)," a song which plays a key role in the film's celebratory finale, as the Portokolas family and members of the local Greek village they are visiting come together for good food, wine, and fun.

Wilson co-wrote the song with Diane Warren, a longtime friend of hers and Vardalos. "I thought, 'If now's the chance to work with Diane, this would be the one because of her connection to all of us,'" says Wilson. "Nia wanted something that was very much about family and how we're always there for each other. That's the sentiment. Oli mazi in Greek means 'everybody all together.' Nia used all Greek songs for the soundtrack. So it was something that we wanted to incorporate, which was bringing Greek lyrics into it. It's a song that feels very international and American."

Wilson says the songwriting process was quick and the ideas came to them easily. "We wrote it at Diane's studio," explains Wilson. "In the lobby, we immediately started talking about the song. She picked up a guitar, she sat down, we started writing. It was crazy because it happened so spontaneously. Diane is a genius. She's an incredible person, she's an incredible writer, and it was really a gift to be able to write with her."

Part of that, at least in Wilson's opinion, is because songwriting for a movie offers different parameters than writing for oneself. "You're given these very specific things to go by," she notes. "Nia says, 'I want it to feel like this. It should feel like it has Greek chords. It should sound like it could be played on Greek radio, but also on American radio.'"

"Diane and I really wanted this chorus to be something that you could sing along to," Wilson continues. "So if you were in a disco or at a party, everybody would be able to pick up on what that chorus is."

Wilson got her wish. On Friday, Dimitri Vegas and Like Mike, a Belgian–Greek DJ duo composed of brothers Dimitri Thivaios and Michael Thivaios, released a dance remix of the track.

My Big Fat Greek Wedding 3 is now playing.

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