The former Hills star and American footballer husband Jay Cutler will give son Camden, one, a little brother or sister in the new year.
On Wednesday evening (20 November), the blonde beauty showed off her bump in a tight-fitted black dress while hosting a Thanksgiving dinner in Los Angeles.
Kristin, 26, looked radiant as she posed for photographers on the purple carpet, happily giving them a side view of her stomach.
The ex-Laguna Beach star hasn't chosen to learn the sex of her unborn child, telling E! News: "I honestly don't care. There's great things about both. Another boy would be fun, Cam would have a little buddy and then I'd be the woman of the house… but of course I want a little girl, so I don't know. Either would be great."
She's has made no secret of how much she loves being a mother, frequently sharing sweet snaps of her little man with fans.
Kristin and Jay, who plays for the Chicago Bears, married in a small ceremony in Nashville in June 2013 and later honeymooned in Italy.
The Chicago-based couple welcomed son Camden in August 2012. They confirmed their second pregnancy in October 2013, saying at the time: "Thank you for all the love!! We are so excited for Camden to be a big brother!"
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