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Could Kate Middleton have let slip that she is having a baby girl? When a well-wisher in Grimsby gave Kate a gift of a teddy bear on Tuesday, the pregnant Duchess replied, "Thank you, I'll take that for my d... "
The local resident, named Sandra Cook, quickly asked, "You were going to say 'daughter' weren't you?"
"No, we don't know yet," said Kate, quickly correcting herself. When pressed further, the blushing royal said, "We're not telling."
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The Duchess' unguarded moment means betting house Ladbrokes have drastically reduced the odds on the baby being a girl. Spokeswoman Jessica Bridge said: "Kate's dropped the biggest hint yet, and the odds have followed suit.
"We'll have egg on our face if their newborn turns out to be a boy, but we're confident there will be a new Princess in the Royal family this summer."
Pregnant Kate received countless presents her on her public engagement in Grimsby, including flowers and both blue and pink gift bags.
The mum-to-be had a touching encounter with one young child, whose parents had both suffered from cancer. "She said I had been very brave, with my dad being poorly," Evie Oxley, 11, revealed.
Kate's openness has now sparked fevered speculation among royal watchers, all eager to find out the sex of the unborn child, which is due in July.
If Kate and her husband Prince William do have a daughter, their baby will officially hold the title of princess.
The Queen recently overturned a 1917 decree which meant that Kate and William's daughter would have been known as Lady, not Her Royal Highness. The announcement about the decree was made on Kate's 31st birthday on 9 January.
"All the children of the eldest son of The Prince of Wales (Charles) should have and enjoy the style, title and attribute of Royal Highness with the titular dignity of Prince or Princess prefixed to their Christian names or with such other titles of honour," a statement said.
Their baby will be third in line to the throne, regardless of gender. In December, The government reached an agreement with all other Commonwealth countries to press ahead with a bill ending discrimination against women in the British monarchy.
Deputy Prime Minister Nick Clegg said it was by "wonderful coincidence" that final formal consents from other Commonwealth realms were received just as William and Kate revealed that they were expecting their first child.
"The government will soon introduce the Succession to the Crown Bill which will make our old fashioned rules fit for the 21st Century," Mr Clegg said. "It will write down in law what we agreed back in 2011 – that if the Duke and Duchess Cambridge have a baby girl, she can one day be our Queen even if she later has younger brothers."
The Succession to the Crown Bill, now at the committe stage, is currently being steered through the House of Lords before it lands on the Queen's desk for final approval.
Kate's coyness is in line with tradition. The sex of a royal heir has always been kept secret and the world will now have to wait until a formal announcement is made when the baby is born in July.