Alexi Ashe and Seth Meyers Credit: Michael Stewart/FilmMagic

Late-night diaper changes! Seth Meyers and his wife, Alexi Ashe, are expecting their first child together, his rep exclusively confirms to Us Weekly.

“Both Seth and Alexi were beaming at last night’s Natural History Museum Gala [in NYC]," a source tells Us. "They are so thrilled to become parents and were so happy to share the exciting news with friends and cast members from SNL last night."

Us broke the news that the Late Night host, 41, and Ashe married on Martha's Vineyard in Massachusetts in September 2013. Several of Meyers' Saturday Night Live costars attended the ceremony, including Amy Poehler, Jason Sudeikis, Andy Samberg, Taran Killam, and Kristen Wiig.

"He's very excited for the next phase of his life," a source told Us at the time. "He's known that she's The One for awhile, but it was all about timing."

Meyers rarely talks about his marriage, but he did share a sweet anecdote from his wedding day while attending a Couture Council luncheon in NYC last year. At the time, he recalled Ashe trying on her wedding gown.

"I will never forget the first time she returned from her fitting, because she was happier than I’ve ever seen her. Which was a little jarring for me, because I had recently proposed to her," Meyers joked. "Turns out getting a ring from me is less exciting than having Carolina Herrera creating your dress."

He also revealed that Ashe got food poisoning the night before their nuptials. "In a testament to my wife’s will and my wife’s strength, she got herself pumped full of fluids, and she rallied and made it to the ceremony," he added. ". . . When she walked out in her Herrera wedding dress, she looked more beautiful than I had ever seen her look."

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