Why William and Kate Chose The Name Louis For Their segundo Son 

This Is Why Prince William and Kate Middleton Chose Louis for the Royal Baby\'s Name

After four days, the little prince’s name has finally been revealed: Louis Arthur Charles.

Prince William and Kate Middleton had several treasured royal family names to choose from when it came to selecting a name for their new son. But Louis — although a traditional name — wasn’t the obvious choice, as it’s big brother Prince George’s middle name.

magazine, says using the same name across the immediate family isn’t unusual. In fact, Queen Victoria incorporated the name Albert (the name of her beloved husband, Prince Albert) in all of her sons’ names. Victoria’s grandson, George V, even incorporated it into his three sons’ names. 

“While she was alive, Queen Victoria wanted all her male descendants to have Albert included in their boys’ names,” Little tells PEOPLE. “Using Louis twice would have been the couple’s choice — they clearly regard it as a nice name.”

Louis is likely a tribute to Prince Philip, whose grandfather was Prince Louis Alexander of Battenberg. The name holds great meaning to William’s own father, Prince Charles, whose beloved great-uncle and mentor, Earl Louis Mountbatten, was assassinated by the IRA in 1979.

Little adds, “Louis is obviously a favorite name and an indirect nod to the Duke of Edinburgh and his side of the family. I did think that Philip might have appeared in there somewhere.”

Royal historian Robert Lacey adds: “It shows the romance of this name associated with the hero and family mentor whom William never met — his father’s ‘honorary grandfather.’

“And maybe Kate enjoyed the French flavor of Louis in these Brexit days. It’s very Champs Elysées! Louis exudes the aroma of strong coffee and the fizz of champagne.”

The names Michael and James (for Kate’s father and brother, respectively) were also highly speculated, but in the end, Will and Kate didn’t choose a name from the Middleton family.

“It is intriguing that there isn’t a Middleton name. You can understand a ‘royal’ name being used for the first son, but there was no pressure for the second son to have a purely royal name,” Little says. “If Kate had felt it was what she wanted she would have gotten it, but clearly she didn’t think Michael or James worked.”

Raising a Royal streaming now on PeopleTV.com, or download the PeopleTV app on your favorite device.

Will and Kate also resisted leading with the trendy name of Arthur, which has been a popular name in Chelsea and neighboring areas of London recently. But they did include it as a middle name.

In addition to its recent popularity, Arthur is also a royal family tradition. Both dad William and grandfather Charles have it as a middle name. Arthur was also the name of Queen Victoria’s third son (and seventh child) and was said to be her favorite child.

Now that they are back home in Kensington Palace with their new baby boy, Prince William and Kate Middleton have begun life as a family of five.

“It completes them,” royal biographer Ingrid Seward tells PEOPLE in this week’s cover story. A friend of the couple notes that Kate, 36, “is one of three siblings, and it’s a good family size. Boy-girl-boy is pretty cool as well.”

Parenthood, the friend adds, “suits them really well. They are enjoying it and are very happy.”

Subscribe to the daily newsletter for the latest celebrity news.