Meghan, Duchess of Sussex attends a National Service of Thanksgiving to celebrate the Platinum Jubilee of Queen Elizabeth II at St Paul’s Cathedral on June 3, 2022 in London, England. The Platinum Jubilee of Elizabeth II is being celebrated from June 2 to June 5, 2022, in the UK and Commonwealth to mark the 70th anniversary of the accession of Queen Elizabeth II on 6 February 1952.

AsKing Charleswas officially crowned head of the British monarchy at his coronation on Saturday, his daughter-in-law,Meghan Markle, and grandchildren,Prince ArchieandPrincess Lilibet, were more than 5,000 miles away in California.

Meanwhile, his wife and children stayed behind in Montecito, where they celebrated Archie’s 4th birthday on Saturday.

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

Prince Harry.GARETH CATTERMOLE/POOL/AFP via Getty Images

Prince Harry, Duke of Sussex attends the Coronation Ceremony of Britain’s King Charles III and Britain’s Queen Camilla inside Westminster Abbey

King Charles was said to be “pleased” his son would be there for his big day, but the wider reconciliation so many have hoped for within the family hasn’t happened. And the absence of Meghan reflects the complex feelings between the couple and the royal family.

“Things are strained,” says a palace insider.

However, a source who knows the royals told PEOPLE Harry “will happily go along with whatever the plan is” and that his main concern about attending was the issue of his security, which was been addressed.

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

With Prince Archie’s4th birthdayfalling on the same day as King Charles' coronation, Meghan will be able to celebrate their son at home alongside his little sister, Princess Lilibet, 23 months.

“It’s an elegant solution,” royal biographer Sally Bedell Smith, author ofGeorge VI and Elizabeth, told PEOPLE, adding that Archie’s birthday “gave them a reasonable out for Meghan not to come.” But 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?”

Prince Harry, Meghan Markle, King Charles and Queen Camilla.Andy Stenning - WPA Pool/Getty

Prince William, Prince of Wales, Prince Harry, Duke of Sussex, Meghan, Duchess of Sussex, King Charles III, Camilla, Queen Consort, Princess Anne, Princess Royal and Princess Beatrice observe the coffin of Queen Elizabeth II as it is transferred from the gun carriage to the hearse at Wellington Arch following the State Funeral of Queen Elizabeth II at Westminster Abbey on September 19, 2022 in London, England.

A palace insider also tells PEOPLE, “It would have been quite significant if Harry hadn’t attended his father’s coronation, but I’m not surprised Meghan isn’t going given the circumstances.”

Archie and 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 Meghan and Harry’s daughter 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.

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At the time, a royal source told PEOPLE it was a “fantastic visit.” The trip allowed Lili to meet her grandfather, who was then known asPrince Charles, and her great-grandmother,Queen Elizabeth, who died in September, for the first time.Prince Harryand Meghan named their daughter in the Queen’s honor, asLilibet was her childhood nickname.

“It was a fantastic visit. The prince was delighted to see his grandson and meet his granddaughter for the first time,” the source said, adding that it was “very emotional” and a “wonderful thing” for Charles to meet Lili.

source: people.com