“Game of Thrones”' Hafþór Júlíus Björnsson and Wife Kelsey Henson Expecting Baby No. 2: 'Couldn't Be Happier'

The couple is already parents to son Stormur

The Mountain is going to be a dad again!

Hafþór Júlíus Björnsson — best known for his role as Gregor "The Mountain" Clegane on Game of Thrones — and his wife Kelsey Henson, 33, are expecting their second baby together, sharing the exciting news on Instagram Thursday.

In the photos, the actor poses next to his wife, who wears an open white shirt that bares her baby bump.

The couple's son Stormur, 3, stands in front of them, holding up a sonogram strip and wearing a black T-shirt that reads "brother."

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Related: 'Game of Thrones' ' Hafþór Júlíus Björnsson Welcomes a Son: A 'Healthy, Strong, Beautiful Boy'

"Life is precious and I couldn't be happier to announce that our family is growing bigger," Björnsson wrote in his caption. "Kelsey is 19 weeks pregnant with a healthy child who we cannot wait to meet! Ps @kelc33 doesn't wanna know the gender this pregnancy so you all gotta wait like me! 🙃❤️."

Henson also announced the news on her page, writing "We are so very happy to share that Stormur will be a big brother in March! He is already taking the role very seriously, cuddling moms belly, blowing raspberries for the baby and pretending to be a baby himself 🥹😂."

In addition to son Stormur, Björnsson also shares daughter Theresa Líf with ex-girlfriend Thelma Björk Steimann.

In 2020, Björnsson and his wife welcomed their son, announcing the news on Instagram.

"Our beautiful baby boy made his grand entrance into the world at 11:19 AM on September 26th 2020 after a short and intense six hours. 3530 grams and 52 cm. The birth was the most powerful, life changing, empowering thing I’ve ever done in my entire life. We are all doing well and settling in at home as three!" the new mom shared.

The actor also shared the story of their son's birth. "After an extremely hard 2 hours and 19 mins of pushing our healthy, strong, beautiful boy arrived weighing 3530 grams, 52 cm long," he said. "To finish the most beautiful, awe inspiring labour was the most wonderful phone call to my daughter to introduce her to her new little brother."

The Game of Thrones star and Henson tied the knot in October 2018 in his native Iceland.

"It is with great pleasure that I now get to call Kelsey Morgan Henson my wife!" Björnsson captioned a photo of himself holding his bride up on their wedding day.

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