Bumping along nicely! Pregnant Katherine Heigl shows off growing belly in striped maxi skirt as she heads to a birthday party 

She's expecting her third child this coming January.

And Katherine Heigl showed off her growing baby bump as she stepped out for a birthday party in Los Angeles with her family on Saturday.

The 37-year-old looked to be in good spirits while out with adopted daughters Naleigh, seven, and Adalaide, four, and husband Josh Kelley, 36.

Baby on board: Katherine Heigl showed off her growing baby bump as she headed to a birthday party in Los Angeles with her family on Saturday

Katherine wore a loose-fitting, sleeveless black turtleneck top, teamed with a figure-hugging black and white striped maxi dress.

The floor-length dress hugged Katherine's curves, showing off the star's burgeoning baby bump.

She finished off the look with a pair of black and white low-top sneakers, and carried a large, black handbag.

Sophisticated: The mom-to-be wore a figure-hugging, black and white striped maxi dress that highlighted her growing bump 

She wore her short, blonde tresses slicked back and out of her face, and hid her eyes behind a pair of black sunglasses.

The Grey's Anatomy alum accessorized with large, gold earrings as well as a coordinating bracelet.

Daughters Naleigh and Adalaide could be seen juggling gift bags and balloons as they walked alongside their parents in Los Angeles.

Growing family: The Grey's Anatomy alum was joined by her two daughters Naleigh, seven, and Adalaide, four

They've got their hands full! Katherine's little girls juggled big gift bags as well as a collection of balloons 

Josh, who sported a white, short-sleeved T-shirt, grey shorts, and grey loafers, had his hands full as well. 

Katherine and Josh announced that the actress was pregnant with her first child back in June, revealing to People that they are having a boy.

The pair tied the knot in 2007, and later welcomed adopted daughters Naleigh - in 2009 - and Adalaide - in 2012.

Lending a hand! Josh had his hands full as well, as the family all helped out while heading to the birthday party on Saturday

Meanwhile, the mom-to-be has been busy working on upcoming CBS drama Doubt, which also stars Laverne Cox and Elliott Gould.

On the upcoming series, per CBS's description, Katherine plays Sadie Ellis, a brilliant attorney at a boutique firm who starts to fall for her charismatic client, Billy Brennan, an altruistic pediatric surgeon accused of murdering his girlfriend 24 years ago. 

Doubt is set to premiere in 2017.  

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