Serena Williams Reveals She Won't Be Attending Archie's Christening: Meghan 'Understands'

For Meghan Markle and Prince Harry, July 5 marks a special day for their son as he will be baptized at his christening.

Meanwhile, for the royal mother of one’s close friend Serena Williams, it will be a day of work as the tennis star, 37, continues to focus on the Wimbledon tournament.

Days ahead of baby Archie’s christening at Queen Elizabeth‘s private chapel at Windsor Castle, Williams told reporters that she will not be a part of the royal festivities.

“No, I’m working on Saturday,” the athlete said when asked if she would be attending Archie’s christening. “ understands work,” the seven-time Wimbledon winner added.

RELATED: Meghan Markle and Prince Harry Plan to Keep Baby Archie’s Godparents a Secret

On Thursday, Meghan made a surprise appearance at Wimbledon to support her good friend when she took on 18-year-old qualifier Kaja Juvan.

“Yes, I knew she was there. It’s always exciting when she comes out to watch and support the tennis so I was happy,” Williams told reporters about seeing the Duchess of Sussex in the stands with friends Lindsay Roth and Genevieve Hillis.

The presence of two of Meghan’s oldest and closest friends heightened speculation the two may have been chosen to be among the godparents at baby Archie’s christening.

Meghan first met Williams at the 2010 Super Bowl in Miami where they immediately hit it off. Last summer, the mother of one and her husband Alexis Ohanian, who both attended the royal wedding, joined Meghan to watch Harry compete in a polo match in Ascot, England. Williams also helped throw a baby shower for her friend in N.Y.C. earlier this year.

RELATED: Meghan Markle & Prince Harry’s Son Archie’s Christening Will Include This Royal Family Heirloom

A source recently told PEOPLE that Meghan and husband Prince Harry chose the Queen’s private chapel because they “wanted an intimate, peaceful setting in a place with such a special connection to Her Majesty.”

The royal parents of Archie, who was born on May 6, will not have to travel far from their Frogmore Cottage home, also on the grounds of Windsor Castle.

The gathering will be attended by around 25 close family members and friends. Royal christenings are typically private, with only close family, friends and godparents in attendance.

“This is a beautiful milestone and they are excited to share it as a family first and then with the world,” the source said.

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Archie will be wearing the same christening robe that his royal cousins Prince George, 5, Princess Charlotte, 4, and Prince Louis, 1, wore for their own ceremonies.

The family heirloom is a replica of the historic royal christening gown first worn by Queen Victoria’s eldest daughter, also named Victoria, in 1841. It was worn by 62 royal babies (including Queen Elizabeth, Prince Charles and Prince William) before it was deemed too fragile to continue using. It was hand-washed in spring water and stored in a dark room between christenings.

The new gown was designed by the Queen’s assistant, Angela Kelly, and Buckingham Palace’s team of dressmakers in 2008.