Charlotte is actually Pippa's middle name and HELLO! wonders if Kate was paying tribute to her sister when announcing the baby's name.
WATCH: Princess Charlotte's cutest moments through the years
That isn't the only special detail about the Cambridges' only daughter. Charlotte's full name is Charlotte Elizabeth Diana – a tribute to her great-grandmother the Queen and William's late mother, Princess Diana.
Pippa married hedge fund manager James Matthews in Berkshire in May 2017. Her nephew Prince George, then aged three, and her niece Princess Charlotte, then aged two, were given starring roles as pageboy and flower girl at the wedding. The Duchess of Cambridge helped to usher the young bridal party into the church on the day.
When Kate married Prince William in April 2011, Pippa was her sister's maid of honour and looked stunning in a cowl-neck satin bridesmaid dress designed by Sarah Burton for Alexander McQueen, that matched the royal bride's dress.
George, Charlotte and Kate at Pippa's wedding
Pippa and James welcomed their first child Arthur Matthews in October 2018 and the family-of-three live in a £17million property in London.
Before Kate became a member of the royal family, she and Pippa shared a flat together on Old Church Street in Chelsea, London.
Their parents Michael and Carole Middleton bought the three-storey property for the sisters for £780,000 back in 2002 and put it up for sale for £1.95million in 2018, but it sold for £1.88million in September 2019.
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