The Duke and Duchess of Sussex have wished Prince Philip a "very happy birthday" on Instagram.
Prince Harry and Duchess Meghan have sent their well-wishes to Harry's grandfather on his 98th birthday, affectionately referring to the Duke of Edinburgh as "grandpa".
The couple - who became parents to their first son Archie last month - shared two photos of Philip, one of him besides Harry and another showing a younger version of the royal dancing with his wife, Queen Elizabeth II.
They wrote: "Wishing His Royal Highness The Duke of Edinburgh, Sir, Grandpa a very Happy 98th Birthday!"
Their birthday message has been liked 400,000 times and royal fans have gushed over the pair's special post.
One wrote: "Love, love the second picture! He makes the Queen so happy. Happy Birthday Prince Philip (sic)"
Another said: "A wonderful man! Happy birthday sir"
A third commented: "Happy birthday and best wishes to His Royal Highness the Duke of Edinburgh! Long live the Prince. 98th is a blessing. (sic)"
Harry, 34, and Meghan, 37, weren't the only ones to celebrate the occasion with his brother Prince William and sister-in-law Duchess Catherine also sharing touching tribute on the Kensington Royal Instagram account that read: "Wishing a very Happy 98th Birthday to His Royal Highness The Duke of Edinburgh!"
The duke's granddaughter Princess Eugenie also posted a message online, writing: "Happy Birthday to HRH The Duke of Edinburgh.
"I found a couple of classic photographs of Grandpa and I on Christmas Day and Trooping the Colour a few years ago now."
The Royal Family's official Instagram account also shared a birthday message, posting photos of the senior royal at Lady Gabriella Windsor and Thomas Kingston's wedding this year and photographed in 1953 - 66 years ago.
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Wishing His Royal Highness The Duke of Edinburgh a very Happy 98th Birthday! #HappyBirthdayHRH The Duke of Edinburgh was born on this day in 1921. In the first picture HRH is pictured at Lady Gabriella Windsor and Thomas Kingston’s wedding this year. In the second picture His Royal Highness was photographed in 1953, 66 years ago.
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