As the countdown to the arrival of the royal baby continues, as Kate Middleton is expected to give birth between July 11 to July 13, many are wondering if the Duke and Duchess of Cambridge know the sex of their baby, and ABC News has news on the baby's gender that may surprise you.

According to royal sources, Kate Middleton and Prince William do not yet know the sex of their baby, even though the Duchess "teased" her fans by wearing pink at her last public appearance at the Queen's Trooping of the Colour celebration.

Royal sources also confirm that when the baby is ready to be born, the first announcement from the palace will come after Middleton has been admitted to St. Mary's Hospital, the same hospital in which her late mother-in-law Princess Diana gave birth to Prince William. The second formal birth announcement will be in the form of a traditional paper with an official palace seal placed on a golden easel outside of Buckingham Palace's gates.

Photographers, security officials and royalty enthusiasts have already swarmed to be near the hospital where Middleton is expected to give birth any day now in the private Lindo Wing of St. Mary's Hospital. According to UPI.com, royal officials will follow a strict protocol once the baby has been born.

"When Baby Cambridge is born, a royal official will appear at the entrance of the Lindo Wing with an envelope bearing the details of the baby, and will give the official announcement," the palace instructs. "The envelope will then be handed to a royal messenger, bound for Buckingham Palace, and the statement will be displayed in the palace's forecourt for the public to see."

The future heir to the throne is expected to bring millions to the British economy, and already thousands have placed their bets on everything from the baby's name (Alexandra is a popular choice for a girl, George for a boy) to its hair color, eye color, height and, of course, whether it will be a prince or princess.

In preparation for the baby, the Duchess has toned down her usual rigorous workout during her third trimester, opting instead for low-impact exercise like prenatal yoga and early morning walk to ensure the health of her baby. She has also given up her beloved daily dose of caffeine even though it is not known whether or not it would affect her baby, as she wants to be on the safe side and have the healthiest pregnancy possible even though she reportedly "did not like the idea of not drinking coffee."

An insider even told US Weekly that Middleton "had a yoga instructor visit her at Kensington Palace once a week."

The Duchess is reportedly "nervous" but "excited" to give birth, having made special preparations for the baby's lavish yet sophisticated nurseries.

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