There's another royal baby in the family!
Princess Beatrice, granddaughter to Queen Elizabeth II and eldest daughter of Prince Andrew and Sarah, Duchess of York, announced the name of their first child with husband Edoardo Mapelli Mozzi Friday.
"Her Royal Highness Princess Beatrice and Mr Edoardo Mapelli Mozzi have named their daughter Sienna Elizabeth Mapelli Mozzi," the royal family announced on social media. "The couple have said, 'We are all doing well and Wolfie is the best big brother to Sienna.' "
The newest member of the British royal family was born Sept. 18 just before midnight local time at the Chelsea and Westminster Hospital in London – a different location from other royal births. She weighs 6 pounds and 2 ounces, per the palace.
👶 Her Royal Highness Princess Beatrice and Mr Edoardo Mapelli Mozzi have named their daughter Sienna Elizabeth Mapelli Mozzi.
👣 The couple have said, “We are all doing well and Wolfie is the best big brother to Sienna.” pic.twitter.com/J7PNxn2EjI
— The Royal Family (@RoyalFamily) October 1, 2021
"The new baby’s grandparents and great-grandparents have all been informed and are delighted with the news," a release from the palace said. "The family would like to thank all the staff at the hospital for their wonderful care."
This is the royal couple's first child together, who will be eleventh in line to the British throne. Mozzi, CEO of architecture/design studio Banda Property, is also father to a young son from a previous relationship with American architect and designer Dara Huang.
"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 palace said.
Princess Beatrice, 33, and Mozzi, 37, tied the knot in July 2020 amid the coronavirus pandemic during a private, low-key ceremony at The Royal Chapel of All Saints at Royal Lodge, Windsor. They were joined by close family including Beatrice's grandparents, Queen Elizabeth and the late Prince Philip.
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Beatrice wore a vintage Norman Hartnell dress loaned by the queen, Buckingham Palace told USA TODAY in a statement at the time.
Mozzi marked their first anniversary on July 17 with an emotional love note on his verified Instagram account.
"I can't believe it has been 1 year,” he wrote with heart, bride and ring emojis. “Every second of every day since has been so full of joy, happiness, laughter and love. You are the kindest, loveliest and most beautiful person in the world. Thank you my darling for every second."
Princess Beatrice's husband pays loving tribute on first wedding anniversary
See her wedding gown: Princess Beatrice borrowed a vintage dress, tiara from Queen Elizabeth
Days earlier, Princess Beatrice showed off her baby bump alongside Mozzi at the Wimbledon tennis championships, wearing a chic black-and-white polka-dotted dress.
Queen Elizabeth now has 12 great-grandchildren, including Prince William and Duchess Kate's 8-year old son George (third in line to the throne) and to Prince Harry and Duchess Meghan's 3-month-old daughter Lilibet.
Princess Beatrice's newborn is the second grandchild of Prince Andrew and Sarah Ferguson. Beatrice's sister, Princess Eugenie, welcomed her first child, a son named August, with husband Jack Brooksbank in February.
Contributing: Kim Willis
Princess Eugenie, husband Jack Brooksbank welcome baby boy, the queen's 9th great-grandchild
This article originally appeared on USA TODAY: Princess Beatrice, Edoardo Mapelli Mozzi reveal baby's name, Sienna