Carrie Brownstein and Amy Poehler helped a couple get married during a book reading event Credit: Jason Merritt/Getty Images; Frederick M. Brown/Getty Images

A wedding to remember! Carrie Brownstein and Amy Poehler were taken by surprise during a book reading event in Pasadena, Calif., on Tuesday, Nov. 3, when two fans ambushed the event, requesting an impromptu wedding ceremony!

Poehler was on hand at the Pasadena Presbyterian Church to help pal Brownstein host a discussion about her latest book, Hunger Makes Me a Modern Girl: A Memoir, conducting an onstage Q&A session with the musician and actress, following a brief book reading.

But both celebs were taken by surprise by one of the questions posed by a couple of female fans in the audience.

"The couple told Carrie they’d heard from a friend that she was an ordained minister," a member of the audience tells Us Weekly. "They asked if they could get married on the spot, as they’d come prepared with their marriage license."

"Amy was visibly excited and shocked, and turned to Carrie [and said] 'You gotta do it!'" the source continues. "The crowd cheered and applauded wildly."

Fortunately for the same-sex couple, Brownstein had her ministry credentials on her (she explained she'd become ordained in order to marry some friends in a couple of weeks), and agreed to marry them as soon as she had concluded her book Q&A!

Kendall Oshiro and Genevieve Hernandez then joined the celebrities on stage, dressed casually in jeans, and Poehler grabbed a couple of bouquets for them from a larger flower arrangement nearby.

Brownstein then took some brief time out to compose some appropriate words, while Poehler sat at the piano. "I only know the first part of 'Greensleeves,'" she announced to the crowd, who roared with laughter.

Moments later, Brownstein returned and married the couple!

"It was a sincere, thoughtful, and impressive speech, considering the spontaneity," our spy says of Brownstein's delivery. "Amy remained seated at the piano, looking emotional and delighted for them."

"The entire ceremony lasted just under 10 minutes," the source continues, culminating in Brownstein declaring the couple married, and Poehler playing piano as the couple kissed.

Watch a clip of the impromptu celebrity ceremony in the video above.

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