Witney Carson discovers sex of 3rd baby with husband Carson McAllister

The Dancing With the Stars pro has sons Leo, five, and Jet, three, with her husband Carson McAllister, and the star took to Instagram to share an adorable baby reveal video ahead of the birth of their third child.

In the clip, the couple were standing on a jetty with their back to their two boys, who opened up an envelope to find out the sex of their upcoming sibling.

Leo produced a shocked reaction when he found out he was to have another brother, but he and Jet didn't let the news slip.

Instead, Leo picked up a blue bouquet of flowers and asked his parents to turn around.

There was some confusion as Jet had picked up the pink bouquet, but a chuckling Carson said: "Another boy! What?! Are we just a house full of brothers?"

"We couldn’t be happier or feel more blessed with all these boys. I love being a boy mom. My greatest honor in life is to raise them."

Former Dancing With the Stars pro Julianne Hough wrote: "Best Boy Mom ever"

YouTuber Whitney Simmons posted: "best mommy raising the best boys!!!!!!! (sic)"

Wrestler Nikki Bella - whose ex-husband is former DWTS pro Artem Chigvintsev - posted: "Aww congrats!"

Brittany Mahomes - the wife of Kansas City Chiefs quarterback Patrick Mahomes - commented: "This was so cute. congrats!!!! (sic)"

Last month, Witney - who is currently competing in DWTS' 35th season, alongside Jimmy Kimmel Live! sidekick Guillermo Rodriguez - confirmed she is expecting her third child.

She told TODAY.com: "We decided we wanted to grow our family. It’s time.

"We know that we want a lot of kids and we thought it was a perfect year to start doing that.

"Then this opportunity came up again to do the show, and it just felt like, ‘You know what? I kind of want to prove to myself that I can do both!’ And I love both.