Preparations are already underway for the future king of England's christening, which is set to take place in the fall, but there's a lot of speculation over who the newborn's six godparents will be – the royal family traditionally chooses three men and three women.
According to British betting firm Ladbrokes, William's brother, Prince Harry, and Kate's sister, Pippa Middleton, are the firm favorites, but the list of other contenders even includes soccer star David Beckham (at 16/1 odds)!
However, Ingrid Seward, editor-in-chief of Majesty magazine, tells PEOPLE that it's unlikely Becks is in the running. "There are no hard and fast rules about this but I just know the royal family has never had a celebrity as a godparent," she says.
But she does admit "there are wild cards" on the shortlist. "Godparents don't have to be your best friend. Quite often it is quite the opposite, it can be somebody quite random."
Prince William certainly has an interesting list of godparents, including Lady Susan Hussey (the Queen's lady-in-waiting), the former king of Greece, Constantine, and Sir Laurens van der Post, the explorer and writer (a close friend of William's father Prince Charles, who was 76 when William was christened).
"You choose godparents for various reasons," William's cousin, jewelry designer and mother of five India Hicks says.
"We chose one that we knew would be there if anything happened to us and be able to take over the mothering for the child, we chose one who was fascinating from a religious point of view and had a very different think on life, could teach the children a different way of looking at religion. We chose a great artist who could inspire them," she says. "I would think they wouldn't be any different from that."
Uncle Harry and Aunt Pippa seem like obvious choices, but Seward says that since they are already so closely related to the baby and will be around all the time, "there is no real need" to have them as godparents as well.
Seward's list of frontrunners includes:
Sophie Wessex, who's married to William's uncle, Prince Edward. "She is a member of the family and is quite child-oriented. I think she would be quite good as a godmother," Seward says.
Zara Tindall, William's cousin and Olympic equestrian champion, who's expecting a baby herself. "William loves Zara, so I think she might be more of a candidate than Harry," she admits.
Thomas van Straubenzee, James Meade or Hugh Van Custem, who are all friends of William's. "They are all part of their very tight-knit group."
Tiggy Legge-Bourke, who's William's former nanny. "William is godfather to one of her children [Tom, who was a pageboy at William and Kate's wedding], plus she has always been there for William and Harry."
Pavlos, Crown Prince of Greece. William is the godfather to Pavlos's son, Prince Constantine, Seward explains, and Pavlov's dad, Constantine, is William's own godfather.
A member of Kate's family. "What about Kate's uncle, Gary Goldsmith? Wouldn't that be funny?" Seward jokes, adding, "Kate might want her brother, James, instead of Pippa, or there might be someone on from Kate's family that we just don't know about."
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