The Duke of Cambridge is yet to meet his niece, but he already shares a sweet connection with Prince Harry and Meghan Markle's newborn daughter, Lilibet 'Lili' Diana Mountbatten-Windsor.
The uncle-and-niece duo share the same birth month, with little Lilibet born on 4 June and Prince William celebrating his 39th on 21 June. June also marks the same birth month as Zara Tindall's second daughter Lena, who was born on 18 June 2018.
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Meanwhile, on Thursday, it will be a bittersweet day for the royal family as it would have been Prince Philip's 100th birthday.
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Little Lili will have to wait a while before she meets her family, as she was born in Santa Barbara, California, where her parents now live full-time with her older brother Archie.
In light of Lilibet's arrival, Prince William and Kate released a statement alongside the Queen, Prince Charles and the Duchess of Cornwall, congratulating the couple on their family of four.
A Buckingham Palace spokesperson said: "The Queen, The Prince of Wales and The Duchess of Cornwall, and The Duke and Duchess of Cambridge have been informed and are delighted with the news of the birth of a daughter for The Duke and Duchess of Sussex."
Prince William and Kate will have to wait before they meet their new niece
Prince Willaim and Kate later added: "We are all delighted by the happy news of the arrival of baby Lili. Congratulations to Harry, Meghan and Archie."
Harry and Meghan's daughter is not the first royal to be born in the US. The Duke's distant cousin, Lord Frederick Windsor and his wife Lady Frederick Windsor (Sophie Winkleman) welcomed their eldest daughter, Maud Windsor, at the Ronald Reagan UCLA Medical Center in Los Angeles on 15 August 2013.
The tot is the Queen's 11th great-grandchild and is the fifth grandchild for the Prince of Wales.
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