Maksim Chmerkovskiy Says Love for Son Shai, 5, 'Only Gets Stronger': 'My Guy and I' hed: Maksim Chmerkovskiy Says Love for Son Shai 'Only Gets Stronger': 'My Guy and I' hed: Maksim Chmerkovskiy Says Love for Son Shai 'Only Gets Stronger': 'My Guy and I'

Maksim Chmerkovskiy/instagram

Maksim Chmerkovskiy is in love with being a dad.

The Dancing with the Stars pro, 42, shared a photo of him and his 5-year-old son, Shai Aleksander — whom he shares with Peta Murgatroyd, 36 — on Monday.

In the photo, Chmerkovskiy lovingly puts his arm around his mini-me as they stand in the sand during a day at the beach.

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

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Reflecting on fatherhood, Chmerkovskiy continued, "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🙏🏼."

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His special father-son moment with Shai comes months after he celebrated a major milestone: Shai's first day of kindergarten.

In September, Shai headed off to school, leaving Chmerkovskiy "tearing up in the parking lot."

Chmerkovskiy posted an adorable picture on Instagram of Shai smiling on his big day, holding up an all-about-me sign that indicated the name of his teacher, his age, the date and what he wants to be when he grows up.

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"First day of kindergarten! Shai's is excited, @petamurgatroyd is devastated, pops (me) is not ok. The whole 'blink and he's an adult' thing is too real. Tearing up in the parking lot….again 😭😭😭," he captioned the cute set of snaps.

Shortly after, Chmerkovskiy shared a video from school drop-off, during which the professional dancer couldn't get over how big his little boy had gotten.

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"Why is he so big? Maybe if I sit down he won't appear so big. Why are you so adult?" Chmerkovskiy asked as he flips around the camera.

"Best job I've ever had," he captioned the video.