Kate Middleton, the Duchess of Cambridge has given birth to her second child - a girl.
The princess was delivered at 8.34am today weighing 8lbs 3oz, Kensington Palace confirmed.
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Kate's daughter was delivered far quicker then her first child - with the baby being born less than three hours after she was admitted to hospital at 6am in the early stages of labour.
George took more than 10 hours to be born but it appears his sister might have taken less then half that time.
The baby girl is a princess, but only because of the Queen's intervention.
Under past rules limiting titles within the royal family, the girl would have been Lady Mountbatten-Windsor.
But the Queen issued a Letters Patent under the Great Seal of the Realm in December 2012 when Kate was around three months pregnant with George, declaring ''all the children of the eldest son of the Prince of Wales 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''.
When William is king, the new Princess might have the honorary style the Princess Royal - which is currently used by Princess Anne. It is customarily given by the sovereign to his or her eldest daughter.
Following a hospital spell for severe morning sickness, Kate continued with her royal engagements throughout the pregnancy, finishing with a visit to the Stephen Lawrence Centre in late March.