They have a son named Shai Aleksander.
The pair first started dating in May of 2012 but ended things a year later. The two rekindled there relationship back in January of 2015 and are now engaged.
He's been linked to superstar Jennifer Lopez and model Kate Upton, but turns out Maksim Chmerkovskiy's heart has always belonged to Peta Murgatroyd.
"They've never really 'broken up,' " a Dancing with the Stars source tells PEOPLE about the professional dancers, who first stepped out as a couple in 2012. "They're with each other a lot and have been for quite some time, including all last season. Tommy [Chong] would tease her about it."
But don't expect Murgatroyd, 28, and Chmerkovskiy, 35, to make a big show of their relationship.
"After some of the more serious commitments Maks made in the past, he's not looking to make any big announcements or labels about things," says the source. "But Peta is his girl and he's never stopped wanting to be around her."
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In fact, one of the things Chmerkovskiy admires most about the dancer is her independent spirit.
"She couldn't care less about making things official or being called his girlfriend," says the source. "She is so the opposite of clingy and is content to just spend time with him and be happy."
Reps for Murgatroyd and Chmerkovskiy have not commented on the relationship.
Maksim Chmerkovskiy, proposed to Peta onstage in Miami on Saturday, Dec. 5, 2015. He got down on one knee in front of 1,500 people following their performance of Sway: A Dance Trilogy and presented her with a custom Cantamessa engagement ring that he designed for especially for her.