Taking to Twitter, Edoardo reposted Beatrice's message and the Queen's statement following the arrival. The royal couple welcomed a little daughter together on Saturday.
Beatrice, 33, shared her joy by tweeting: "So delighted to share the news of the safe arrival of our daughter on Saturday 18th September 2021, at 23.42, at the Chelsea and Westminster Hospital, London. Thank you to the Midwife team and everyone at the hospital for their wonderful care."
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Buckingham Palace announced the royal baby's arrival – and the Queen's twelfth great-grandchild – in a statement that read: "Her Royal Highness Princess Beatrice and Mr Edoardo Mapelli Mozzi are delighted to announce the safe arrival of their daughter on Saturday 18th September 2021, at 23.42, at the Chelsea and Westminster Hospital, London. The baby weighs six pounds and two ounces.
"The new baby's grandparents and great-grandparents have all been informed and are delighted with the news. The family would like to thank all the staff at the hospital for their wonderful care.
"Her Royal Highness and her child are both doing well, and the couple are looking forward to introducing their daughter to her big brother Christopher Woolf."
The couple attended Wimbledon earlier this year
The royal baby is the fourth great-grandchild the Queen has welcomed in 2021. Beatrice's younger sister Princess Eugenie and her husband Jack Brooksbank had their son, August, in February, while Zara and Mike Tindall's third child, Lucas, arrived in March.
The new arrival is the first child for Beatrice and the second for her husband Edoardo. The property developer is already the proud dad to five-year-old Christopher Woolf (affectionately known as Wolfie), from his previous relationship with American architect Dara Huang.
The tot is 11th in line to the throne, meaning that Eugenie will move down to 12th place. Eugenie and Jack's son, August, will also move further down in the line of succession to 13th place.
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