Lance Bass to Officiate Jax Taylor and Brittany Cartwright's 'Vanderpump Rules' Wedding

The pop star will help Jax Taylor and Brittany Cartwright say 'I do!'

Lance Bass is ready to help two Vanderpump Rules stars say "I do!"

Two sources confirm to ET that the *NSYNC singer will officiate Jax Taylor and Brittany Cartwright’s wedding in Kentucky on June 29. Bass and Taylor are partners together in several business ventures, including Just Add X non-alcoholic mixers.

When ET's Brice Sander spoke with the couple at the 4th Annual World Dog Day celebration in West Hollywood last month, they said wedding planning was going "really well."

"We're just waiting for all of our RSVPs to come back in and then we're gonna start the seating charts," Brittany said. "That's, like, one of the hardest things. And then after that, we're pretty much golden."

However, there were still a few important details left to iron out, like what the couple’s Pump Rules co-star, Tom Sandoval’s, place is in the bridal party after his and Jax’s heated argument at the season seven reunion taping. At one point, Jax stormed off the reunion set and proclaimed that Tom was no longer his best man.

"We’ll talk about it," Jax said last month. "We’re gonna talk about it. Of course, he’s in my wedding, he’s one of my best friends. I love him to death."

"He’s definitely in the bridal party," Brittany clarified, though neither she nor Jax would say if he was still the best man.

Another thing the couple still had to figure out is their married name. Jax’s legal name, Jason Cauchi, is included on the Beauty and the Beast-themed wedding invitations, and the couple told ET they’ll likely go by Jax’s legal moniker after the wedding, in part to honor his late father, Ronald Cauchi.

“It’ll be our family name,” Jax said. “For sure, our kids will have my last name.”

One guest who sadly may not be in attendance at the nuptials, however, is Vanderpump Rules matriarch Lisa Vanderpump. ET has learned that the reality star is taking a step back from filming, following the unexpected death of her mother, Jean, earlier this week. Vanderpump's reps confirmed the news to ET, saying the reality star was "shocked and devastated" by the news and asking for privacy as she coped with the loss.

ET has also learned that Vanderpump Rules cameras are still shooting season eight with the rest of the cast, leading up to Jax and Brittany's wedding. Vanderpump may attend if she's feeling up to it, and if it does not conflict with any memorials for her mother.

See more on the couple in the video below.

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