Jessica Paré is going to be a mom!

The 33-year-old Canadian actress, best known for her role as Megan Draper on the hit AMC period drama "Mad Men," is expecting her first child with musician boyfriend John Kastner, her rep confirmed to Us Weekly Tuesday.

Paré and her Canadian beau have kept their relationship very much low-profile that their baby announcement on Instagram last month flew under the radar for a while, People reported.

In the post, Kastner shared a cute snap of his 7-year-old daughter, Summer Lee, proudly wearing a T-shirt with the words "I'm going to be a big sister," while he and her girlfriend are seen hugging in the background.

Paré and Kastner started dating in May 2012. The "Wicker Park" actress was previously married to writer-producer Joseph M. Smith from 2007 to 2010, Page Six reported. Kastner, on the other hand, tied the knot with Summer's mom, Nicole DeBoer, in 1999, but the two split in 2012.

Kastner is the singer for Montreal hardcore punk band the Asexuals as well as singer-guitarist for Montreal alternative band Doughboys and alternative band All Systems Go!.  He also acts as the manager for the Canadian new wave group Men Without Hats.

Like her beau, Paré has also talent in music. As fans of "Mad Men" can recall, she showed off her singing skills in the Season 5 premiere of "Mad Men," in which her character Megan threw her husband Don Draper (Jon Hamm) a party for his 40th birthday, and famously sang a sexy rendition of the 1960s song "Zou Bisou Bisou" in front of most of the employee s of the firm, Daily Mail reported.

The track reached No. 1 on Billboard's World Digital chart, and in an interview with Rolling Stone at the time, Paré joked, "I thought, 'I should get a band together!'"

Meanwhile, "Mad Men" is set to wrap up its 7-season run in spring 2015. In June, Paré opened up about the Golden Globe-winning series coming to an end.

"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 New York City. "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 we're growing."