'Big Brother' Couple Jessica Graf and Cody Nickson Marry in Malibu Ceremony

Jessica Graf and Cody Nickson solidified their place in the Big Brother showmance hall of fame Sunday, tying the knot after announcing they were expecting their first child together.

Nickson, 33, and Graf, 27, made things official in an intimate outdoor ceremony at The Chateau Le Dome at Saddlerock Ranch in Malibu over the weekend, they told PEOPLE. On the guest list of less than 100 people were Big Brother alums Mark Jansen and Elena Davies, and Amazing Race co-star Conor Daly.

See the wedding photos here.

"Our wildest dreams came true today — we're married!" the couple, who met in season 19 of Big Brother and went on to win season 30 of Amazing Race, told the publication. "Being surrounded by our closest family and friends and sharing this special day with them was all we ever wanted. We are so lucky to have found each other in the most unconventional of ways but we did. We found our forever in each other and can't wait to begin this new chapter of our lives."

Of the decor, Graf described the ceremony and reception as "very romantic."

"Fall in L.A. is just so gorgeous out, so I wanted to be dancing under the stars all night long," the bride said. "I wanted for it to be dripping in flowers, and string lights and lots and lots of candles. I wanted it to look just very romantic. Like a daydream."

For a sentimental touch, two seats in the ceremony were left empty for two departed loved ones, Nickson's brother Dylan and Graf's late father.

Bridesmaids wore all black, and Graf carried a bouquet of black orchids.

"I know that's very untraditional, but I like the picturesque feel of it all," Graf said of her use of black in the decor and dresses.

Big Brother head of casting Robyn Kass officiated the wedding.

"I'm thrilled to have officiated Jess and Cody's wedding," Kass told the magazine. "I'm just so happy for them."

"We wanted it to be somebody that was a part of the special process that even brought us here," Nickson added.

For their first dance, the couple got down to "Shut Up and Dance" by Aaron Watson.

"He sang it to me when we were in the Big Brother house, and we danced to it, and, it just always sat in the back of my mind as one of our special moments," Graf said of the choice.

"There was a long time in our relationship where everything we knew about each other, the outside world also new," Graf added of their time in the house. "If you were a live feeder, there were no secrets. It wasn't until we finally got some alone time outside of the house where we could start getting to know each other beyond what everyone else knew, and I think that was pretty special."

The couple is heading off to a romantic honeymoon in Bora Bora before they settle into their Texas home, which is under renovation before their new baby is born.

"In five years I am going to be on baby probably number three and exhausted. And, hopefully still pretty," Graf joked.

"I mean, no matter what we do, we're both going to be successful at it," Nickson chimed in. "So, I just don't know what those things are yet. But, whatever it is, we're going to be successful. And, we're going to have good, healthy, strong family."