Apart from their sixth wedding anniversary, the couple also marked their son Finn's fourth birthday.
"How it started [to] how’s it going," Nikki wrote in her post, which featured throwback photos of her and BJ. "Happy 6th anniversary, babe @bj_albert. Still can’t believe we have two kids now, LOL. Love you!"
In a separate post, Nikki compiled clips of Finn from the time he was a baby. Aww.
"Happy fourth birthday to my sweet and silly boy, Finn," Nikki said. "It was such a joy seeing him step into the role of big brother this year. Love you, Manong!"
Nikki recently gave birth to their second child, Madeline "Maddie" Elle, in October.
Happy wedding anniversary, Nikki and BJ, and happy birthday, Finn!