The two quietly tied the knot in June.
They "do" -- again!
Michael Phelps and Nicole Johnson celebrated their wedding with a beautiful ceremony in Cabo San Lucas, Mexico, on Saturday.
WATCH: Michael Phelps and Nicole Johnson Are Married, Quietly Tied the Knot in June
Johnson wore a gorgeous, custom Julie Vino Bridal gown that featured an intricate lace cut-out bustier with a sweetheart neckline and a curve-hugging skirt with a thigh-high slit. She finished her pretty, modern bridal look with a beaded headband and strappy heels. Phelps looked dapper as well, sporting a tan suit, white button-down shirt, pale blue tie, and caramel-hued dress shoes, all perfect for the warm day.
Their beautiful beachside nuptials were photographed by the bride's maid-of-honor, Ellice Boone. After the ceremony, the couple took to Instagram to share photos from their big day.
"Truly the happiest day of my life @m_phelps00 thank you @boonestudios for capturing this day," Johnson captioned her pic, adding a kissy face emoji.
Phelp's post was just as sweet. He shared a shot of him and his bride walking down the aisle after saying their "I do's," captioning it, "My best friend.... I love you!!"
PHOTOS: Inside Michael Phelps' Final Olympics and Life as a New Dad
It was revealed on Wednesday that the couple secretly tied the knot in June. The 31-year-old swimmer confirmed the happy news in a Facebook Live video on Thursday.
"I've been married for a while, a couple months," Phelps said with a big smile. "I had to keep it a secret from y'all. I had to keep it hush-hush from you guys. But Nicole and I are married, we are officially married, and now we are getting the chance to just kind of kick it and hang out now."
While the decorated Olympian didn't hint at their Mexican wedding ceremony at the time, he did tease that another baby might soon be on the way.
"Gotta always have something, guys. Thank you for the beautiful comment," he explained of his surprise marriage. "Baby No. 2 may be coming soon. Who knows, though?"
WATCH: Michael Phelps Talks Secret Marriage to Nicole Johnson, Says Baby No. 2 'May Be Coming Soon'
Phelps and Johnson got engaged in February 2015 and welcomed their adorable son, Boomer, this past May.
"She said yes," Phelps captioned a cute shot of himself and his lady love shortly after he popped the question.
And of course, many adorable family moments followed:
WATCH: Michael Phelps and Son Boomer Enjoy Retirement: We Didn't Wanna Get Out of Bed This Morning!
ET has reached out to Phelps' rep. Congratulations to newlyweds!
See more on the sweet family of three in the video below.