The British royal family celebrated Prince Louis' birthday in a very special and unforgettable way.

The royal was the youngest child of Prince William and Kate Middleton, and sibling to Prince George and Princess Charlotte.

Boss Baby

As the youngest Cambridge turned two, The Royal Family official Twitter account paid tribute by reposting some adorable photos of the little tot.

Prince Louis was seen wearing a checkered blue button-down shirt with his hands painted in the colors of the rainbow --which is also to honor health workers and frontliners who are fighting the battle against COVID-19.

 
"Happy Birthday to Prince Louis. HRH is the Queen's seventh great-grandchild. Today he turns two! The photos below were taken by the Duchess of Cambridge earlier this month," the photo was captioned.

Uh-Oh! Did the Royal Family Get Confused?

However, Prince Louis -- who was born on April 23, 2018 -- was Queen Elizabeth II's sixth great-grandchild and not seventh.

His cousin Lena Tindall, whose parents are Mike and Zara Tindall, was the Queen's seventh great-grandchil.

Royal Blunder Spotted!

Eagle-eyed fans immediately spotted the blunder and pointed out the mistake.

"I'd like to correct the Royal Family. Prince Louis is the Queen's 6th great-grandchild, not 7th. Lena Tindall was born two months after Louis," one user wrote.

Another one responded: "Yes! That's what I was saying. But only for almost two months. Lena was born on June 18."

Although there was a bit of confusion with the said post, royal watchers greeted the young royal on his birthday.

"Happy birthday Louis loved watching his excitement last year on the balcony of Buckingham Palace. What a lovely little boy," one user posted.

Another royal fan pointed out that Prince Louis resembles her father: "Whenever I see Princess Charlotte's photo, I always see Her Majesty! But with Prince Louis, I see Prince Philip. Happy birthday!"

Others also praised the Duchess of Cambridge for a job well done in capturing the lovely photos of Prince Louis.

"Happy Birthday, youngest of Prince's! He is one good looking little guy! The Duchess of Cambridge always knows how to make the most amazing photos!"

The Queen's Great-Grandchildren

The 94-year-old monarch has a total of eight great-grandchildren, and half of them are commoners.

Aside from the young Cambridges and one-year-old Lena, Queen Elizabeth II's other great-grandkids are Savannah and Isla Elizabeth, whose parents are Peter and Autumn Phillips; Lena's older sister Mia; and Archie Harrison, whose parents are Prince Harry and Meghan Markle.

Prince Charles' Sweet Birthday Greetings to the Prince Louis

Another member of the royal family greeted Prince Louis on his special day.

His grandfather and heir to the throne, Prince Charles, posted a touching black and white photo of him and the young royal.

"A very Happy Birthday to Prince Louis, who turns two today. The young Prince enjoys a hug from his Grandfather, The Prince of Wales," the official Twitter account of the Clarence House posted.

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