ForMeghan MarkleandPrince 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 friendSerena Williams, it will be a day of work as the tennis star, 37, continues to focus on theWimbledontournament.

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

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On Thursday, Meghan made asurprise appearanceat 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.

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A source recently told PEOPLE that Meghan and husbandPrince Harrychose the Queen’s private chapel because they “wanted an intimate, peaceful settingin 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.

“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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Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex, pose with their newborn son Archie

Archie will be wearing thesame christening robethat his royal cousinsPrince George, 5,Princess Charlotte, 4, andPrince Louis, 1, wore for their own ceremonies.

source: people.com