Prince Louis Arthur Charles is royal baby's name, Kensington Palace reveals

The Duchess of Cambridge and husband Prince William have decided to name their baby boy Louis Arthur Charles, Kensington Palace said on Friday.

"The baby will be known as His Royal Highness Prince Louis of Cambridge," the palace said.

The couple's third child weighed eight pounds, seven ounces and was born at 6:01 a.m. ET on April 23 at St. Mary's Hospital in London.

William and Kate married in 2011. Their other children are Prince George, 4, and Princess Charlotte, who will be three years old next month. All three children wereborn at the same hospital where William and younger brother Prince Harry came into the world.

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Kate and William's third child,Queen Elizabeth's sixth great-grandchild, is fifth in line to the throne, after grandfather Prince Charles, father Prince William and the two older siblings.

Prince Harry, who will marry American Meghan Markle next month, is sixth. On Thursday it was announced that Prince William would serve as best man for Harry at the May 19 wedding.

The palace didn't elaborate on the significance of the names but Louis pronounced LOO-ee pays tribute twice over to Prince Charles, who has Arthur as one of his middle names.

The choice also honours Louis Mountbatten, Charles's great-uncle and beloved mentor, who was killed by an Irish Republican Army bomb in 1979.

Bookmakers had been doing a brisk trade in bets on the new prince's name, but Louis wasn't among the favourites. The royal couple has used it before, as one of George's middle names.

Arthur, Albert and James had been considered front-runners.

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