She has chosen the name Sienna Elizabeth Mapelli Mozzi. “We are all doing well and Wolfie is the best big brother to Sienna,” she added in thetweetannouncing the news.

Beatrice, 33,welcomed her first childwith husbandEdoardo Mapelli Mozzion September 18.

Edo, as he’s affectionately called, wrote his own touching name announcement onInstagramFriday: “Our life together has just begun, and I can’t wait to see all the amazing things that await us.”

Princess Beatrice and Edoardo Mapelli Mozzi.David M. Benett/Dave Benett/Getty

Princess Beatrice d’York and Edoardo Mapelli Mozzi

Edo’s father is Count Alessandro Mapelli Mozzi, and as his oldest son, Edo will inherit the family’s ancestral seat, the 18th-century Villa Mapelli Mozzi palace in northern Italy.

“Edoardo is the only male descendent taking the family into the next generation,” his father previously toldThe Daily Mail.“He is a count — his wife will be a countess automatically and any of their children will be counts or nobile donna.”

Immediately following the birth announcement ofPrincess Beatrice’s daughter, betting odds put the names Matilda, Florence, Arabella and Cecelia astop predictions. (Elizabeth was also a frontrunner.)

Princess Beatrice’s younger sister,Princess Eugenie, welcomed her first child earlier this year with husbandJack Brooksbank. The couple named their sonAugust Philip Hawke, revealing the special meaning behind his moniker on Instagram.

“He is named after his great grandfather and both of his great x5 grandfathers,” Eugenie, 31, explained.

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The royal family’s new addition — she is currently11th in the line of succession to the British throne— isQueen Elizabeth’s 12th great-grandchild and the second grandchild forSarah FergusonandPrince Andrew.

source: people.com