There's a lot of baby bump action happening on the set of the new CBS sitcom Accidentally On Purpose: Both Jenna Elfman and Ashley Jensen are expecting!

And mom-to-be Jensen, 40, has been grilling Elfman, 38, who already has a son, Story Elias, 2.

What happens when your underwear digs into you? she asks in the video, above.

Elfman's tip? "Get bigger underwear!"