Serena Williams Breaks a Major Wedding-Guest Rule in a Plunging Gown With Y2K-Coded Sleeves

As Venus Williams married Andrea Preti in a waterside Palm Beach ceremony over the weekend, her sister and longtime tennis partner, Serena Williams, was by her side during the five-day festivities. In first photos shared of the bridal party by Vogue on December 23, the Serena Ventures founder made a striking appearance in a strapless sweetheart gown with Y2K-inspired sleeves—which also broke a major wedding-guest rule.

Acting as the bride’s maid of honor, Serena made sure her sister’s big day went smoothly and delivered a speech during the nuptials, as seen in photos shared on Instagram by Vogue on Tuesday. The mom-of-two turned heads as she proudly posed in a gown that was a sartorial faux pas: Wearing a white dress to someone else’s wedding. As she posed next to Venus in bridal party photos, Serena flouted wedding-guest dress code in a plunging sweetheart gown with subtle ruching along the bodycon column silhouette. She paired the classic white dress with a surprising Y2K-coded accessory, adding a pair of detached arm warmers that were made out of a sheer white material.

READ: Serena Williams Congratulates Sister Venus on Marriage to

While wearing white as a wedding guest is typically frowned upon, it appears that Serena’s white gown was by design and fully approved by the bride. In Venus’s group photo with her bridesmaids, all the women could be seen dressed in the typically bridal hue with similar white necklaces, hinting that Venus wanted a uniform look for her wedding.

Serena Williams Congratulates Sister Venus on Marriage to Andrea Preti, Says Seeing Her ‘Built-in Best Friend’ So ‘Loved’ Means ‘Everything’ to Her

The Williams sisters have each other’s backs on the court — and down the aisle.

In a new Instagram post shared on Tuesday, Dec. 23, Serena Williams gushed about her older sister Venus Williams following Venus’ wedding to actor Andrea Preti. “My sister’s keeper,” Serena, 44, began the lengthy caption. “Venus, where do I even begin?”

Serena went on to describe the way she’s seen Venus lead with “grace, strength, and a heart bigger than any trophy” as the two professional tennis players grew from “backyard courts” to “the biggest stages in the world.”

READ: What Novak Djokovic said the umpire shouldn’t have done after Serena Williams

“Watching you step into this next chapter surrounded by love felt like watching the sun rise…steady, powerful, and full of promise,” she continued.

“You’ve been my built-in best friend, my protector, my teacher, and my reminder to always walk in purpose. Seeing you this happy, this loved, this radiant… it means everything to me. To love, to partnership, to laughter, and to a lifetime of choosing each other every single day. I couldn’t be prouder to stand beside you, not just today, but always,” the caption concluded.

Serena wore a white strapless mermaid gown with a sweetheart neckline, flowing cape and detached lace sleeves. Pearl jewelry and pointed-toe heels accessorized the design, as did her old-Hollywood-inspired blonde waves and red manicure.

Serena and Venus Williams Team Up Once Again — But This Time, It’s Off the Court: ‘We’re So Much More Than Sport’ (Exclusive)

While usually taboo for anyone but the bride to wear white, the choice seemed intentionally made by Venus, 45, who also had their two other sisters, Lyndrea Price and Isha Price, niece Justus, and mom Oracene dressed in white.

In the months leading up to the wedding, Serena told PEOPLE during the launch of her and Venus’ new podcast, Stockton Street, in September 2025, that she was busy with “so much planning” ahead of her older sister’s wedding. She noted that Venus leaned on her for help as she’s known as someone who can “get things done.”

Serena also recalled one of their recent planning calls, saying her sister wanted her input on “literally 14 hairstyles.” She explained, “So she sent me her options and within 30 minutes I had them not only done, but in a PDF file what hairstyle looked best on everyone.”

“I’m the person that arranges things, I’m like the planner. I plan everything like the event. I’m the person that gets things done,” she added of her role.

Venus and Preti were first linked in July 2024 when they were seen boating in Nerano, Italy, along the Amalfi Coast. After months of rumors, she finally confirmed the relationship during a post-match interview in July 2025 when she referred to Preti as her “fiancé.”

In 2025, Venus and Preti actually got married twice. The first ceremony came in September, when they tied the knot in Italy. They were wed again on Dec. 19 in a courthouse ceremony in West Palm Beach, Fla., following a full week of festivities before the big day.

Prior to the courthouse ceremony, Venus, Preti, and their guests enjoyed a yacht day, romantic dinner, and a bridal shower.

“For me, the courthouse ceremony was very unique, emotional, and deep,” Preti told Vogue, adding that “it was the second-best day” of his life, after the wedding itself.