Mad Men star Jessica Pare is pregnant and expecting her first child with musician boyfriend John Kastner, her rep confirms exclusively to Us Weekly Credit: Michael Loccisano/Getty Images

Mrs. Draper is pregnant! Mad Men star Jessica Pare is expecting her first child with boyfriend John Kastner, her rep confirms exclusively to Us Weekly.

The Canada native, 33, has kept quiet about her Canadian musician beau, but the couple have stepped out on occasion for red carpet events. They most recently attended Audi's Celebration of Emmys Week in L.A. on Aug. 21.

Pare has also showed off her own musical talents since moving from Montreal to L.A. a decade ago. Despite teasing to London's Evening Standard in 2013 that she plays the ukulele "poorly," she famously sang a sexy rendition of the 1960s song "Zou Bisou Bisou" in season 5 of the AMC drama.

As Mad Men fans can recall, Megan Draper embarrassed her husband Don Draper (Jon Hamm) with the serenade at his 40th surprise birthday party. Pare lip-synced to a track she previously recorded while filming the March 2012 episode, which reached No. 1 on Billboard's World Digital chart. "I thought, 'I should get a band together!'" she joked to Rolling Stone at the time.

Pare joined the Mad Men cast as a secretary at Sterling Cooper Draper Pryce in 2010, and became a central character after the shocking season 4 finale when Don weds Megan nearly out of the blue. Back in June, she opened up about the series coming to an end in spring 2015.

"I do feel like the end of Mad Men is sort of a coming of age," she told Elle at a Baume & Mercier event in NYC. "There was before Mad Men, and there's after, and that's what we're talking about here tonight in terms of the milestone moments in a woman's life. We're moving and and we're growing."

This will be the first child for Pare. She was previously married to actor Joseph M. Smith from 2007 to 2010.