"We can confirm that Peta and Maks have had their baby boy, Shai Aleksander Chmerkovskiy, born on Wednesday, January 4 at 5:34AM [PT]. Per the couple, 'This is, without a doubt, the best thing that has ever happened to us!'" a representative for the two Dancing with the Stars pros toldUs Weekly.
Chmerkovskiy and Murgatroyd both shared the big news on Twitter as well several hours after Shai's birth.
Fans have been anticipating the little bundle of joy's arrival because Chmerkovskiy's brother Val posted an Instagram video on Tuesday saying that he was "expecting to be an uncle very soon" and "family means the most" to him. Val ditched a show in Richmond to be at the hospital when Murgatroyd delivered the baby.
"My sister-in-law Peta Murgatroyd is literally delivering the baby as soon as I'm done with this video, hopefully," Val said in the video.
Murgatroyd checked herself into the hospital on Monday. The bad boy of the ballroom posted a photo of his longtime love on Instagram in which the mom-to-be was putting on some mascara while sitting in her hospital bed.
Chmerkovskiy and Murgatroyd got engaged in December 2015, confirmed they were expecting their first child together in June 2016, and have been snapping adorable photos left and right of each other ever since.
When Murgatroyd posted the first picture of her baby bump in July of last year, she said the parents-to-be "couldn't be happier."
Chmerkovskiy then told Us in September he was absolutely ready to become a father, that he had been ready since age 21. The pro dancer was actually looking forward to changing diapers and other paternal responsibilities.
Chmerkovskiy and Murgatroyd began dating back in 2012 and had an on-again, off-again relationship before going steady in Spring 2015.
Whether Murgatroyd will compete on the next edition of Dancing with the Stars this spring remains uncertain. Chmerkovskiy finished the latest Season 23 in ninth place with celebrity partner Amber Rose.