By Kelsey Glein
Aug 09, 2016 @ 1:15 pm
Stefanie Keenan/Getty Images

Talk about one major surprise. Molly Sims revealed today that she is expecting her third child with her movie-producer husband Scott Stuber, and the 43-year-old couldn't be more excited by the unexpected news.

The star took to Instagram today to make the happy announcement, sharing a beautiful photo of herself showing off her very tiny baby bump in a tight black dress. " this happened!!! Baby Stuber #3 is on its way!" she captioned the snap, which pictures her holding a giant "3" balloon. "#LOVE #grateful #CANNOTBELIEVETHIS #ourhailmary."

"It’s a Hail Mary!" she told People about her pregnancy. "I’m so happy—we’re so blessed. We were so shocked, but we’re thrilled."

The couple is already parents to 4-year-old son Brooks Alan and 16-month-old daughter Scarlett May, and Sims plans to document their journey to becoming a family of five on her very own YouTube channel that will launch next week. Their new bundle of joy is due at the end of the year.

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Congratulations to the growing family!