Although the sex of the royal baby is yet to be known, we do know what the unborn baby's official royal title will be, and it's believed to be the first of its kind in royal history.
Buckingham Palace announced Sunday that the royal title of Prince William and Kate Middleton's child will be His or Her Royal Highness the Prince or Princess of Cambridge.
The baby's chosen Christian name is inserted after Prince or Princess, making it His or Her Royal Highness the Prince or Princess "Name" of Cambridge.
"The Queen declared by Letters Patent on December 31 2012 that 'all children of the eldest son of The Prince of Wales should have the style, title and attribute of Royal Highness with the titular dignity of Prince or Princess prefixed to their Christian names,'" a palace spokesman said.
The former Mayor of Cambridge, Councillor Sheila Stuart, says the unborn baby will be the first prince or princess for Cambridge.
"When we did a lot of research after it was first announced that the couple were to get the title, nothing like that was found," Cambridge News reports. "There were some dukes of Cambridge but not a prince or princess."
The palace is being extremely careful in planning media coverage of the birth, trying hard to control what will inevitably be a circus, according to sources. The first announcement will only come after Kate has been admitted to the hospital in the early stage of labor. The palace wants to avoid the media's catching her being admitted while having contractions.
That will be followed by a second announcement: the birth. The public will only learn of the birth after the queen and the Middleton family have been informed, according to royal protocol.
But in keeping with royal tradition, there will be an element of theater to it all. The birth announcement will be signed on official Buckingham Palace note paper and - with cameras rolling - it will be driven to the palace where a liveried footman will put it on an easel in the palace forecourt. The easel was last used when Prince William was born.
The birth announcement will include sex, weight and time of birth. There may a few additional literary flourishes. When William was born the announcement included the words "he has blue eyes and cried lustily."
And as for the baby's first name, the couple has a list of favorites. The betting shops have their money on Alexandra if it's a girl and George if it's a boy.
ABC News' Jeffrey Kofman contributed to this report.