Peta Murgatroyd professed her love for "true soul mate" Maksim Chmerkovskiy while wishing him a happy birthday on Tuesday.
"To my best friend...my partner, for the remainder of the most incredible years to come. You are forever the light that makes my soul ignite, you're the text book definition of my true soul mate," Murgatroyd wrote.
"I never believed in one until I met you," she admitted. "My love for you is never ending. #HappyBirthdayMaks."
Murgatroyd followed up with a photo of Chmerkovskiy holding their infant son, Shai Aleksander.
Chmerkovskiy had shared the same picture last week, saying he's "the happiest person that's ever lived" since becoming a father."...and to the best Father in the world Happy Birthday, Shai is so fortunate to have you as his guardian and protector for life. I see you with him and cry with the amount of love that is in your eyes. Our love for you is for eternity, forever the 3 of us are together," Murgatroyd captioned her post.
The "Dancing with the Stars" pros welcomed Shai on Jan. 4 after announcing Murgatroyd's pregnancy in June.
"Real life: I took this photo 8 days post birth. I left the hospital looking 5 months pregnant. Many people think a woman should shrink right back to her pre-birth weight immediately. That is just not the truth for most," she wrote.