Prince William and Kate posted on their official Twitter page @kensingtonroyal: “Wishing a very happy birthday to The Princess Royal today!”
User @royalinstablog shared a video underneath where Anne is mistakenly introduced as the Prince of Wales, as well as wishing her a happy birthday.
Fortunately, the Princess seemed to see the funny side.
User @skylargabor replied: “Always loving this story and love her.”
Another user @sapphireblues3 wrote “Happy birthday to Princess Anne, the badass Royal”, alongside a montage of the princess over the years.
Twitter account @sarah_delore shared a picture of Anne wearing sunglasses captioned “Happy birthday to the coolest Royal!”, to which @jaxbraidwood replied: “She could have been 007.”
Many fans posted touching stories of their personal encounters with the Princess, proving her dedication to her family and the British people.
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“I will always remember with fond memories our meetings and HRH’s insightfulness on all topics including my research into preventing preeclampsia.”
The Koh-i-Noor is one of the biggest cut diamonds in the world with a name that means ‘Mountain of Light’ in Persian.
Originally from India, it is now part of the British Crown Jewels.