In a "very, very sweet" moment at Dear Evan Hansen on Broadway, Rosario Dawson briefly serenaded New Jersey Sen. Cory Booker on stage, a source says
Celebrities Visit Broadway - January 5, 2019
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In a “very, very sweet” and improvised moment on Saturday while attending Dear Evan Hansen on Broadway, Rosario Dawson briefly serenaded New Jersey Sen. Cory Booker during a cast meet-and-greet, telling him, “I love you,” an onlooker confirms to PEOPLE.

The source says Dawson sang, “I love you, te amo” — Spanish for “I love you” — to Booker in an “impromptu, made-up-on-the-spot” tune.

According to Page Six, which first reported the news, the two were meeting the cast after the show.

The 39-year-old actress and the politician, 49, were joined by two special little guests: Booker’s niece and Dawson’s daughter, Lola. While it was Booker’s second time seeing the show, it was Dawson’s first — and the first-ever Broadway production for Lola, according to the source.

Dawson and Booker, whose relationship status is unclear, weren’t physically affectionate with each other, the source says. “But they were … a very effusive bunch, hugging every cast member, telling each one specific things about each performance, [being] really personable.”

Dawson also seemed to have a rapport with Booker’s niece, according to the source.

This isn’t the first time Dawson and Booker have enjoyed each other’s company in recent days, Page Six reported: They attended a movie together on Thursday in New York City.

The two have known each other for years, according to Page Six (and they seem to be fans of one another’s social media: each follows the other on Instagram and recently re-posted the same tweet to their Instagram Stories).

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Reps for Booker and Dawson did not immediately respond to PEOPLE on Tuesday.

This year Booker, a possible contender for the presidency in 2020, has been linked to the poet Cleo Wade and Chanda Gibson, who runs the Council of Urban Professionals, according to Page Six and the Washington Post.

Booker, meanwhile, is no stranger to celebs: In March 2017, during a playful exchange on Twitter, Booker asked Mindy Kaling to have dinner with him.