Lillibet Diana Mountbatten-Windsor, the newest member of the royal family, is also the second baby in line to the throne to have been born in the USA.
The Duke and Duchess of Sussex welcomed a new baby girl in California on Friday.
Meghan Markle's press secretary made the announcement adding mum and baby, who will be known as Lili, are doing well.
Lili is eighth in line to the throne, and shares her home of birth with another royal child - who is 51st in line, seven-year-old Maud Windsor, reports The Mirror.
They are the only people in line to the throne who were born in the USA.
Maud Windsor was born in Los Angeles in 2013 and is the daughter of Lord Frederick and Sophie Winkelman.
Lord Frederick is the son of the Queen's cousin Prince Michael of Kent and grew up in Kensington Palace next to Prince Harry and Prince William.
Sophie, who is also known as Lady Frederick Windsor, is a British actress, best known for playing Big Suze in Peep Show.
When Maud was born she was the 42nd in line but following the birth of other royal members including Archie, Prince Louis and Princess Charlotte she has been bumped down nine places.
Her family returned to the UK before her younger sister Isabella was born and she goes to the same school and is in the same year as Prince George.
Maud was bridesmaid for Princess Eugenie wedding to Jack Brooksbank.
