Peta Murgatroyd and Maksim Chmerkovskiy Ask Son Shai to 'Please Pause' Growing Up as He Turns 6

Phillip Faraone/Getty, Maksim Chmerkovskiy/instagram

Maksim Chmerkovskiy and Peta Murgatroyd are mesmerized by their growing boy.

Both the Dancing with the Stars pros took to Instagram on Wednesday to celebrate son Shai Aleksander on his 6th birthday.

Sharing a photo of the birthday boy smiling sweetly and wearing a birthday badge, Murgatroyd wrote, "My favorite sweet smart funny boy is 6 🎉🎉🎉."

"Slightly teared up this morning thinking about how the early years are over," she continued. "I made Shai promise though that he won't get any bigger than 6…. I said 'I will still throw you birthday parties each year but you have to stay this way forever.' He said 'Ok Mummy'🥹."

"Life is short, I want to sit in these precious moments forever ❤️," Murgatroyd concluded. "Happy 6th Birthday Shai 🎁."

Chmerkovskiy shared an equally heartfelt tribute to his little boy, writing, "Happy birthday to my kind, smart, beautiful and incredibly funny 6-year-old!"

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"You've been an amazing part of our life with @petamurgatroyd and we are so proud of the boy you're growing up to be," the proud dad wrote. "I know these 6 years flew by but I've experienced so much happiness just from being around you, so much emotion I've never felt before and I will always be there for you for as long as I live."

Chmerkovskiy noted the bond between him and Shai is "unlike anything I've experienced."

"This love is heartachingly beautiful. This day is one of my favorite days every single year," he beamed. "I love you beyond words! P.S. Please pause on the whole growing up thing for a moment 😭😭😭."

In November, Chmerkovskiy shared a photo on Instagram where he lovingly put his arm around his mini-me as they stood in the sand during a day at the beach.

"My guy and I. My heartbeat ❤️," he wrote alongside the photo.

Reflecting on fatherhood, Chmerkovskiy added, "This love is unlike anything else and only gets stronger, if you do it right. Fatherhood is easily hardest and most rewarding job I've ever had. Instant reward with best long term ROI though (in my @garyvee voice ;)."

Chmerkovskiy ended by sharing his thoughts on the difference between a dad and a father.

"A father and a dad are so not the same things," he said. "If you have kids, go be amazing at the most important job you've ever had🙏🏼."