Where'd that baby bump come from?!

Hills alum Audrina Patridge, who's pregnant with her and fiancé Corey Bohan's first child, showed off her growing belly on Instagram in a navy-striped maxi dress.

The 30-year-old recently opened up about impending motherhood, telling Brit + Co, "I can’t wait to have a mini version of [me and Corey]! We’re so excited to watch our baby learn, grow, laugh and explore.”

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The couple, who have been dating since 2008, announced they were expecting in December just a month after getting engaged while out to dinner with her family.

Scroll down to see what the rest of The Hills cast looks like now!