Buckingham Palace confirmed that Beatrice, 33, and her husband Edoardo Mapelli Mozzi, 38, welcomed their first baby together on Saturday.
Beatrice then tweeted on Monday to say she’s “delighted” and to thank the midwife team at Chelsea and Westminster hospital.
Eugenie, 31, has since congratulated her big sister and brother-in-law in a statement shared on Instagram, saying they’re going to “have so much fun” together.
“To my dearest Beabea and Edo,” she wrote. “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 added another note addressed to the baby: “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.”
Beatrice is already stepmother to Mapelli Mozzi’s five-year-old son Christopher Woolf. The couple announced the pregnancy announcement in May this year, following their wedding in July 2020.
The news came a month after Eugenie gave birth to her first child, August, with her husband Jack Brooksbank.
The sisters’ mother, the Duchess of York, recently said she “loves being a grandmother”.
“I’m so proud of how Eugenie and Jack have turned out to be such brilliant parents, and of course Beatrice and Edo are having a baby soon,” she told Australian Women’s Weekly.
“I love being with my grandson August, [six months] and also my step-grandson Wolfie, who is five. I have such fun with both of them.
“August already reacts to me dressing up for him in colourful headbands and hats. When I say funny things or make funny movements, he laughs and laughs.”
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