Princess Beatrice Welcomes First Baby With Husband Edoardo Mapelli Mozzi; Eugenie Congratulates Sister

Princess Beatrice is officially a mom.

Princess Beatrice, 33, and her husband Edoardo Mapelli Mozzi, 38, have welcomed their first child together. Their baby girl, who weighed 6 pounds and 2 ounces, was delivered Saturday night at London's Chelsea and Westminster Hospital. Her name was not immediately revealed.

"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," Buckingham Palace said in a statement to People Monday.

The palace added that the newborn and the new mom "are both doing well" and that the couple is "looking forward to introducing their daughter to her big brother Christopher Woolf."

Princess Beatrice was already a stepmom to Mozzi's young son from a previous relationship with architect and designer Dara Huang.

The new mother also confirmed her safe delivery and the arrival of her baby girl on Twitter.

Princess Beatrice and Mozzi's daughter, who will be 11th in line to the British throne, is Queen Elizabeth's 12th great-grandchild and the second grandchild for Sarah Ferguson and Prince Andrew. The Duke and Duchess of York became first-time grandparents earlier this year when Princess Beatrice's younger sister, Princess Eugenie, welcomed a son named August with husband Jack Brooksbank.

Princess Eugenie penned a sweet message for the couple and her new niece. She shared a snap of Princess Beatrice and Mozzi on Instagram and accompanied it with a heartwarming caption.

"My dearest Beabea and Edo⁣, congratulations on your new angel. I can't wait to meet her and I'm so proud of you. We're going to have so much fun watching our children grow up. Love Euge," she wrote.

"To my new niece, ⁣I love you already and think you're just awesome from the photos. We're going to have so much fun ⁣together. Love, your Auntie Euge," she added.

Princess Beatrice announced her pregnancy in May. The announcement raised some eyebrows at the time because it came on the same day as Prince Harry and Meghan Markle's third wedding anniversary.

However, an unnamed royal source told Page Six that Princess Beatrice had delayed her pregnancy announcement until after her grandfather Prince Philip’s funeral, which took place on April 17.