The Duke and Duchess of Cambridge welcomed their baby girl on Saturday 2 May, revealed the chosen name for their princess yesterday, and have now officially registered her birth.
Kensington Palace revealed the news via Twitter this afternoon: "The Duke and Duchess of Cambridge have formally registered the birth of Princess Charlotte.
"The Duke of Cambridge signed the birth register at Kensington Palace, witnessed by a Registrar from Westminster Register Office."
Charlotte's official title will be: Her Royal Highness Princess Charlotte of Cambridge.
Kate was admitted to St Mary's hospital at 6am on Saturday morning, and gave birth to Charlotte just some two-and-a-half hours later at 8.34am.
Kate and William's first son, prince George, came to the hospital to visit, before returning to Kensington Palace some 45 minutes later.
Soon after, Kate and William left the hospital with their baby girl, but posed for photos before making their way back to the Palace.
Buckingham Palace formally announced the birth of their daughter with the traditional gold easel on the forecourt.
Queues formed outside the Palace as royal well-wishers gathered to view the official announcement.
The birth was also announced on the BT Tower with the message "it's a girl".
Kate and Willis personally thanked the public for their support, with a message from Kensington Palace saying: "The Duke and Duchess are hugely grateful for the messages of congratulations they have received from people all over the world.
"It means a great deal to them that so many people have celebrated the arrival of their new daughter."
Prince Harry has also already gushed about his new niece, saying: "She is absolutely beautiful."
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