"Pretty HUGE news!!!" she captioned the pic. "We're expecting baby #3 in November!!!"
Smart already has two children, 3-year-old Chloe and 1-year-old James, with her husband Matthew Gilmour. She married Gilmour, who is from Scotland, in 2012 after the pair met doing missionary work abroad.
"We were friends first, we were both serving Mormon missions in France, so for 2 years our relationship was platonic," Smart wrote in a recent Instagram post. "He invited me to visit him in Scotland when he had completed his time in France and returned to his family in Scotland. When I walked off the plane in Aberdeen, Scotland and he was waiting for me I knew I had come home (not the country), I knew he was immediately my best friend, and everything I could ever want in a spouse."
Gilmour is the perfect fit for Smart and together they've made a family that Smart (like most mamas) is incredibly proud of and grateful for.
"These people are my whole world. Whenever I look at them I realize how fortunate I am. I hope I never forget what a blessing a safe, healthy, happy family is," she wrote in another Instagram post. "There truly is nothing more precious in my life than my children," she captioned another.
With another precious baby on the way, we couldn't be happier for Smart and her family.
Congratulations on baby #3! 🎉