Whitney Port is pregnant! See 'The Hills' star's sweet Instagram announce

/ Source: TODAY

Lauren Conrad isn't the only "Hills" alum with a baby on board! Conrad's former reality TV co-star Whitney Port just announced her own happy news.

Port showed off her baby bump in a photo she shared on Instagram Thursday.

"Oh hey! Just standing by the window in my underwear, with a BABY in my belly!!!" she said in the caption. "DM me if you know what I'm supposed to do with this thing for however many years I'm supposed to be in charge."

RELATED: Lauren Conrad shows off 'cutest baby bump ever' in Instagram pic

In a post on her blog, Port added that she and husband Tim Rosenman weren't exactly expecting to be expecting.

"I peed on a stick and now I’m going to be a Mom!" she explained. "Timmy and I were a bit shocked, but so excited to begin this journey."

Now she's looking ahead to motherhood, including how she'll answer one inevitable question.

"When two people love each other so much and the love becomes too great to fit inside both people, it spills over into a THIRD person," she wrote. "This is how I am going to explain where babies come from to the little baby that is now growing inside my belly..."

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This will be the first child for Port and her husband. Rosenman worked as a producer on "The Hills" spin-off "The City," and started dating Port in 2012. They married in 2015.

"I can’t wait to be a Mom," Port added, "but the fact that there is another person inside there is seriously crazy!"

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