01/10/2013 05:27 EST | Updated 03/11/2013 04:47 EDT

Kate Middleton Pregnant: The Duchess Of Cambridge's Baby Will Be A Princess If Female

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Britain's Prince WiIliam, the Duke of Cambridge, (L) poses for pictures with his wife Catherine, Duchess of Cambridge, as they leave the King Edward VII hospital in central London, on December 6, 2012. Prince William's pregnant wife Catherine left a London hospital on Thursday, four days after she was admitted for treatment for acute morning sickness. AFP PHOTO/Leon Neal (Photo credit should read LEON NEAL/AFP/Getty Images)

The royal baby has yet to arrive, but he or she is already breaking long-standing tradition.

Queen Elizabeth II has decided should the Duchess of Cambridge give birth to a baby girl, the child will be referred to as Princess or Her Royal Highness. The Queen put forth the decree on Dec. 31, 2012 but it was revealed on Jan. 9, 2013, Kate's 31st birthday, reports US Weekly.

The Queen's decree replaces an almost century-old practice established by George V stating only the eldest son of the Prince of Wales would be called a Prince, while a daughter would be referred to as a Lady (this from The Telegraph).

Some have speculated the Queen's gesture indicates the monarchy's move towards greater gender egalitarianism.

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