The couple's daughter arrived less than a month after her big brother Archie celebrated his second birthday on 6 May. But unlike Archie, Lilibet was born in the United States.
Meghan, 39, gave birth to Archie at the Portland Hospital in 2019, when Harry and Meghan were living together at Frogmore Cottage in Windsor. His little sister, meanwhile, was born in the Santa Barbara Cottage Hospital in California, where the family now reside.
WATCH: Prince Harry and Meghan Markle reveal baby's gender
But what is about the children's nationality? And do they hold the same status?
Since Archie was born in the UK he automatically became a British citizen, and given that his mother is American he is also eligible to become a US citizen.
Meghan pictured with her eldest child, Archie Harrison
For Meghan to be able to pass down her citizenship to her son, she had to have lived in the US for 10 years prior to his birth, which, of course, she did. Archie, therefore, is a dual British and American citizen.
The couple's daughter Lili will benefit from the same law and will be both a US and British dual citizen, like her brother.
The couple's son was born at the Portland Hospital in London
Announcing their daughter's safe arrival on the Archewell website, Harry and Meghan said: "On June 4th, we were blessed with the arrival of our daughter, Lili. She is more than we could have ever imagined, and we remain grateful for the love and prayers we've felt from across the globe. Thank you for your continued kindness and support during this very special time for our family."
A spokesperson further confirmed: "Lili was born on Friday, June 4 at 11:40 a.m. in the trusted care of the doctors and staff at Santa Barbara Cottage Hospital in Santa Barbara, CA. She weighed 7 lbs 11 oz. Both mother and child are healthy and well, and settling in at home.
Prince Harry and Meghan welcomed their daughter on 4 June
"Lili is named after her great-grandmother, Her Majesty The Queen, whose family nickname is Lilibet. Her middle name, Diana, was chosen to honor her beloved late grandmother, The Princess of Wales."
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