Her Majesty, Prince William and Kate Middleton among royal well-wishers for Meghan Markle's 40th birthday

Meghan Markle is 40!

To mark the occasion, Queen Elizabeth II, Prince William and Kate Middleton shared tributes of their own to the Duchess of Sussex, who is celebrating her milestone with husband Prince Harry and children Archie, two, and Lilibet, two months, quietly at home in Montecito, California.

Taking to Twitter, the Royal Family profile — Her Majesty's official account — posted some adorable shots of Meghan with the Queen, Harry, and Archie.

"🎈 Wishing The Duchess of Sussex a very Happy Birthday today!" the message said.

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The Duke and Duchess of Cambridge, meanwhile, shared a message of their own to their Kensington Royal Twitter page, writing, "Wishing a happy 40th birthday to The Duchess of Sussex! 🎂"

The message was accompanied by an image of Meghan wearing a lei on Bondi Beach, during the Sussexes' 2018 tour Down Under.

Prince Charles and Camilla, Duchess of Cornwall shared a well wish too on their official Clarence House Twitter account.

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"Wishing The Duchess of Sussex a very happy 40th birthday. 🎈" they wrote, alongside an image of Meghan alone smiling at the camera.

All the messages from the three households were also cross-posted as Instagram Stories to their respective official accounts. It is unclear if they have had any private correspondence.

Other royals from the extended Windsor family have yet to post any messages to the Duchess.

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Sources told Page Six earlier this week that Meghan, with her husband and two children, is celebrating her birthday quietly at home, particularly considering the presence of COVID-19 worsening in California, and the fact that Meghan gave birth to baby Lily only two months ago.

The Sussexes have historically marked milestones like these out of the public eye: for Meghan's 37th, the couple attended Harry's friend's wedding in Surrey.

Meghan celebrated her 38th birthday — her first as a mum — with a private day at Frogmore Cottage with Harry and Archie.

Last year, like this year, the Sussexes celebrated at home together in Montecito.

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