Meghan Markle and Prince Harry.Photo: Mike Coppola/Getty

NEW YORK, NEW YORK - DECEMBER 06: Meghan, Duchess of Sussex attends the 2022 Robert F. Kennedy Human Rights Ripple of Hope Gala at New York Hilton on December 06, 2022 in New York City. (Photo by Mike Coppola/Getty Images for 2022 Robert F. Kennedy Human Rights Ripple of Hope Gala)

While the royal family (includingPrince Harry) markedKing CharlesandQueen Camilla’scoronationon Saturday,Meghan Marklewas back home in Montecito, California, ringing in sonPrince Archie’s fourth birthday.

As she’s done in years past, the Duchess of Sussex, 41, planned a laid-back celebration at home for her young son with close friends and family.

“It’s going to be a low-key party at home,” a source told PEOPLE. “They’ll have friends around them and Meghan’s mom, Doria [Ragland]. Meghan will definitely have support that weekend.”

“They are so sweet together. Archie loves Lili. He’s such a sweet boy. When she’s not around, he asks, ‘Where’s Lili?’ " the source added.

Prince Harry.Ben Stansall - WPA Pool/Getty Images

Prince Harry, Duke of Sussex attends the Coronation of King Charles III and Queen Camilla

Meghan’s decision to stay back in California whilePrince Harryattended his father’s coronation reflects the complex feelings between the couple and the royal family.

“Things are strained,” says a palace insider.

Those closest to the couple know that the media backlash Meghan faced in the U.K. duringQueen Elizabeth’s funeral last year — and in the seven months since — played a significant role in her decision not to come.

“Meghan wants to be there to support her father-in-law, but at the same time, the scrutiny she receives outweighs the support,” the close friend says. “There’s always going to be that other side challenging their reasoning, and who wants to put themselves in that position?”

The Duke of Sussexwore a morning suitfor the occasion, following the dress code for most of the congregation. PEOPLE understands Harry was requested to wear a morning suit — and that he didn’t make any specific asks regarding his outfit. He adorned the suit with his Afghanistan service medal along with the Golden Jubilee, Diamond Jubilee and Platinum Jubilee medals as well as his KCVO neck decoration and star.

Meghan Markle, Prince Harry, Queen Camilla and King Charles.Anwar Hussein/WireImage

Meghan, Duchess of Sussex, Camilla, Duchess of Cornwall, Prince Harry, Duke of Sussex and Prince Charles, Prince of Wales

Prince Archie and Princess Lili were last in the U.K. duringQueen Elizabeth’sPlatinum Jubileecelebrations in June 2022. Thesignificant tripwas Princess Lili’s first visit to the U.K., as she was born in California on June 4, 2021, and had yet to visit her dad’s homeland. Archie was born in the U.K. on May 6, 2019, but hadn’t been back since late 2019.

During the Duke and Duchess of Sussex’s time in the U.K. last June, they held asmall birthday partyfor Lili, who turned 1 during the trip. The couple, who relocated to Meghan’s home state of California after stepping back from their royal roles in 2020, invited close friends and family to gather for a “casual, intimate backyard picnic” atFrogmore Cottage, a spokesperson said.

Fans got another glimpse of the festivities in the Netflix docuseriesHarry & Meghan, which aired in December 2022. The Duke and Duchess of Sussex sharedintimate family photosthroughout the six-episode series, including from Lili’s birthday party.

Prince Harry.RICHARD POHLE/POOL/AFP via Getty Images

Prince Harry, Duke of Sussex talks to Britain’s Princess Anne, Princess Royal at Westminster Abbey

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Upon the death ofQueen Elizabethin September, Harry’s father became King Charles — and as grandchildren of the monarch, Archie and Liliwere afforded the titles of prince and princess.

“The children’s titles have been a birthright since their grandfather became monarch,” a spokesperson for the Duke and Duchess of Sussex told PEOPLE. “This matter has been settled for some time in alignment with Buckingham Palace.”

source: people.com