Olympian Missy Franklin Shares She Pregnant, Expecting Baby Girl No. 2 in Adorable Halloween Reveal: 'Over the Moon'

Missy Franklin is going to be a girl mom of two!

On Thursday, Oct. 31, the former Olympic swimmer, 29, announced on Instagram that she's pregnant and expecting her second baby girl with husband Hayes Johnson. For the reveal, the couple and their daughter Sarah Caitlin, 3, dressed up as superheroes to celebrate Halloween and held up a sonogram image.

"We couldn’t be happier to share that we’re adding another superhero to the family!!" the proud mom wrote under the sweet family photos. "Baby girl Johnson number two making her entrance in March🩷."

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She added that Sarah "couldn’t be more excited to be a big sis, and she will be the BEST big sister."

"We are absolutely over the moon and cannot believe our blessings. So thankful to be growing our family," she continued in her caption. "Happy Halloween from the three, soon to be FOUR, of us!!🫶🏻."

Franklin was just 17 years old at the 2012 London Summer Olympics where she won an impressive four gold medals for the United States and became a household name, but, as she told PEOPLE in 2020, she can barely swim now due to previous shoulder injuries she sustained.

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"I really can't," she said. "I mean, my shoulders are in so much pain that I can maybe hop in the pool and swim easy for 20, 30 minutes, but that's about as much as my old broken shoulders can handle at this point."

Franklin, who earned her fifth and final gold medal at the 2016 Rio Olympics and announced her retirement in December 2018, is clear on the possibility of returning to swimming: "Absolutely not."

"I never got the second shoulder surgery that I needed and I just — I don't really see getting back in the water at this point in my life being the best thing for my physical or my mental health," she explained. "I kind of feel like I've given everything I possibly could to the sport and now it's to do good outside of the water."