Princess Eugenie and her husband Jack Brooksbank welcomed a baby boy on 9 February.
The royal shared a touching black-and-white photo of her newborn son's fingers sweetly clasped in her and Jack's.
Buckingham Palace also confirmed the news in a statement, however, there was no mention of Eugenie's sister, Princess Beatrice.
Princess Eugenie gave birth on Tuesday
The statement read: "Her Royal Highness Princess Eugenie was safely delivered of a son today, 9th February 2021, at 0855hrs at The Portland Hospital. Jack Brooksbank was present. The baby weighs 8lbs 1oz.
"The Queen, The Duke of Edinburgh, The Duke of York, Sarah, Duchess of York, and Mr and Mrs George Brooksbank have been informed and are delighted with the news.
"This is Princess Eugenie and Jack Brooksbank’s first child, The Duke of York and Sarah, Duchess of York’s first grandchild, and the ninth great-grandchild for The Queen and The Duke of Edinburgh. Her Royal Highness and her child are both doing well."
Eugenie and Beatrice are very close
While Beatrice isn't mentioned in the official statement, it's of course expected that Eugenie's beloved sister would have been among the very first to have been told the happy news.
The two siblings are incredibly close, and Beatrice was her maid of honour when Eugenie married her husband, Jack, in Windsor in 2018.
Eugenie and Jack first announced the pregnancy in September 2020, sharing an adorable photo of the Princess holding a pair of teddy bear slippers on Instagram.
It's thought that Beatrice and doting mum Sarah, Duchess of York, would have thrown Eugenie a virtual baby shower.
Baby showers have become popular in the UK in recent years but due to the current lockdown in England, expectant mothers have been unable to see friends and families unless they live in the same household.
However, Beatrice and Sarah may have arranged for the celebrations to take place virtually, perhaps over Zoom.
The trio share an incredibly close bond but have been unable to see one another amid the current restrictions. Eugenie and Jack are currently residing at the Duke and Duchess of Sussex's Windsor home, Frogmore Cottage, while Sarah lives nearby at Royal Lodge.
Meanwhile, Beatrice and her husband Edoardo Mapelli Mozzi have an apartment at St James's Palace in London.
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