Although Prince Louis is less than three years younger than his older sister, Princess Charlotte, his birth certificate contains several notable differences.

In fact, Louis’ official record also varies in multiple ways from that of his eldest sibling, Prince George, raising curiosity among royal watchers.

For those who may need a refresher, Louis, now six years old, is the son of Prince William and Kate Middleton—officially known as the Prince and Princess of Wales. He was born at 11:01 a.m. on April 23, 2018, at St Mary’s Hospital in London.

The similarities

Louis’ full title was recorded on his birth certificate as “His Royal Highness Prince Louis Arthur Charles of Cambridge,” mirroring the format used for his siblings, George and Charlotte.

George’s certificate stated his title as “His Royal Highness Prince George Alexander Louis of Cambridge,” while Charlotte’s read “Her Royal Highness Princess Charlotte Elizabeth Diana of Cambridge.”

Following their father Prince William’s appointment as Prince of Wales—a title he inherited after King Charles III ascended the throne in 2022—the siblings’ territorial designation could now be updated to “of Wales” instead of “of Cambridge.”

On all three birth certificates, their mother, now 43, is listed as “Her Royal Highness Catherine Elizabeth, The Duchess of Cambridge,” while their father, 42, appears as “His Royal Highness Prince William Arthur Philip Louis, Duke of Cambridge.”