Molly Sims couldn't hold in her emotions while announcing that she's expecting her third baby.

"This is happening. This is like our Hail Mary," the 43-year-old actress exclaimed in a video posted to her YouTube channel on Tuesday morning. "We can't wait to meet you!"

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Sims admitted that the baby news came as a shock to her and husband Scott Stuber. "We never expected it would happen. We didn't even know," she shared. "This was such a true surprise. I think that's why I'm so emotional."

The "Las Vegas" star plans to share her pregnancy journey with fans in a series of video posts, and is open to any advice when it comes to raising three children. "We're going to have three babies," she said in almost disbelief. "He or she will be here before you know it. Now I'm going to do the happy baby Stuber dance."

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A photo posted by Molly Sims (@mollybsims) on

Sims and Stuber's new bundle of joy will have 4-year-old Brooks Alan and 16-month-old Scarlett May as his or her older brother and sister.

A photo posted by Molly Sims (@mollybsims) on

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