Liam Neeson and Son Daniel Support Pamela Anderson at Final Performance of Her Play (Exclusive Source)

Liam Neeson is giving Pamela Anderson her flowers.

The 73-year-old actor showed up to support his Naked Gun leading lady, whom he is also dating in real life, as she took her last bow in the Tennessee Williams play Camino Real during the Williamstown Theatre Festival.

A source close to the festival confirms to PEOPLE that Liam and his son Daniel attended the show’s final afternoon performance on Sunday, Aug. 3.

Anderson, 58, was announced to star in Camino Real, in which she plays Marguerite Gautier, back in April. Performances began on July 17, and wrapped with Sunday’s show.

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The play follows an American sailor named Kilroy (Nicholas Alexander Chavez) as he navigates a bizarre, surreal town, the Camino Real. Throughout the play, which is fragmented as it features non-linear scenes, Kilroy meets various characters including historical figures like Don Quixote (Frankie J. Alvarez) and Lord Byron (Ato Blankson-Wood).

Anderson’s last stage production before Camino Real was her turn as murderess Roxie Hart in Broadway’s Chicago — a role she described as “a dream fulfilled.”

The Last Showgirl star is also currently starring alongside Liam in The Naked Gun, which hit theaters Friday, Aug. 1, and is a sequel to the 1988 film of the same name starring Leslie Nielsen.

Liam plays Lt. Frank Drebin Jr., the son of Nielsen’s Frank Drebin from the original Naked Gun films, while Anderson plays his love interest, Beth. The film grossed $28.5 million worldwide its opening weekend, per The Hollywood Reporter, and boasts a 90% rating on Rotten Tomatoes.

A source told PEOPLE on July 29 that Anderson and the Taken actor are “in the early stages” of dating in their “budding romance… It’s sincere, and it’s clear they’re smitten with each other.” The Naked Gun costars have been “enjoying each other’s company,” continued the source, as the costars promoted the crime-spoof comedy.

Meanwhile, 28-year-old Daniel, who Liam shares with his late wife Natasha Richardson, gave the new couple his enthusiastic approval from the audience of Watch What Happens Live with Andy Cohen on Sunday, Aug. 3.

In an interview with The New York Times, Anderson raved about Liam’s presence on the movie’s set. “He has so much charm and so much charisma that you kind of just fall into it. I can’t explain it because I’ve never experienced it before,” she said. “To do comedy, it gives you a lot of energy when you’re in something so joyful and silly.”

Added Anderson, “Liam has done over 100 movies, and I hope he’s inspired to do even more.”

The Naked Gun is now playing in theaters.