Third in line to the throne, the new arrival will be known as His Royal Highness Prince George of Cambridge.
His parents announced their 2-day-old's moniker shortly after his 87-year-old paternal great-grandmother, The Queen, visited the family at Kensington Palace Wednesday – when, PEOPLE reported, it was believed she would be discussing possible names.
The chosen name carries a lot of sentimental meaning to William's granny – it was the name picked by her beloved father when he became King George VI in 1936. His real name was Albert, and his story was told in 2010's Oscar-winning Best Picture The King's Speech.
"George was a bit of a giveaway – it was bandied around so much and we expected it," Joe Little, managing editor of Majesty magazine tells PEOPLE. "And it is a nice tribute to the Queen's father and grandfather [George V]."
Alexander is believed to have been picked by the couple to honor the Queen, whose middle name is Alexandra.
Little says the name Louis "is a nice tribute" to the Queen's husband, Prince Philip, whose grandfather was Prince Louis Alexander of Battenberg. Louis is also part of the baby's father's full name of William Arthur Philip Louis. It also has great meaning to William's own father, Prince Charles, whose uncle and mentor, Earl Louis Mountbatten, was assassinated by the IRA in 1979.
Kate and William decided on a name fairly quickly – William's parents took a week to announce his name, while, back in 1948, Prince Charles wasn't named for a month!
Still to be seen: if Kate and William will give their first-born a nickname. George's daddy has a couple of them – his mom, the late Princess Diana, used to call him "Wills," while Kate reportedly calls him "Big Willie" – and his uncle Harry's real name is Henry.
Tell us, do you like the baby's new name?
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