Princess Beatrice has revealed a sweet nickname for her daughter, Sienna, in a handwritten thank you card.
One Twitter user shared the note, which enclosed an image of the royal baby's footprints.
It read: "Thank you so much for thinking of us at this remarkable and special time. We are so thankful to have welcomed this little person into our family. She is a little rockstar! With love, Beatrice, Edo, Wolfie and Sienna."
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WATCH: Princess Beatrice and Edoardo announce royal baby's name
The Princess, 33, and her husband, Edoardo Mapelli Mozzi, welcomed their first child on 18 September 2021 at the Chelsea and Westminster Hospital. The tot's full name, Sienna Elizabeth Mapelli Mozzi, was announced almost two weeks after her birth. She is the Queen's 12th great-grandchild and is currently 11th in line to the throne.
Property developer Edoardo also has a six-year-old son, Christopher Woolf, known as Wolfie, from his previous relationship with American architect, Dara Huang.
Beatrice and Edoardo have not shared an image of their daughter publicly, but proud grandmother, Sarah, Duchess of York described her as "very, very beautiful".
MORE: Princess Beatrice and Edoardo Mapelli Mozzi's surprising connection as babies
MORE: Edoardo Mapelli Mozzi shares stunning photo from family ski break with Princess Beatrice
Beatrice and Edoardo welcomed baby Sienna in September
The couple enjoyed a holiday in Swiss ski resort, Verbier, with the Duchess of York and Beatrice's younger sister, Princess Eugenie and her husband, Jack Brooksbank, at the beginning of the year.
Edoardo shared a dreamy-looking photo from their family trip on Instagram Stories, showing some snow-covered trees against the inky blue sky in the Alpine village.
Princess Beatrice married Edoardo in a private wedding ceremony at the Royal Chapel of All Saints at Royal Lodge in Windsor in July 2020. The Queen and the late Duke of Edinburgh were among the handful of guests at the service due to pandemic restrictions at the time.
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