Following the news of the birth of Eugenie and her husband Jack Brooksbank's first child, Sarah took to Instagram to like the first official picture.
The royal baby was delivered at The Portland Hospital, close to Eugenie and Jack's current home, Frogmore Cottage in Windsor.
WATCH: Princess Eugenie welcomes first child with Jack Brooksbank!
The official 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."
Sarah, Duchess of York liked Princess Eugenie's first baby photo
The newborn is the first grandchild for Andrew and Sarah, and the ninth great-grandchild for the Queen and the Duke of Edinburgh.
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.
The couple married at St George's Chapel in Windsor on 12 October 2018, after dating since 2010.
Princess Eugenie and Jack Brooksbank are pictured with Sarah
Speaking to HELLO! in September after their eldest daughter confirmed that she was expecting, Sarah spoke of her and her ex-husband's joy, saying: "Soon to be Grandpa and Granny are absolutely overjoyed."
The palace's formal statement at the time read: "Her Royal Highness Princess Eugenie and Mr Jack Brooksbank are very pleased to announce that they are expecting a baby in early 2021.
Eugenie and Jack announced they were expecting their first child last September
"The Duke of York and Sarah, Duchess of York, Mr and Mrs George Brooksbank, The Queen and The Duke of Edinburgh are delighted with the news."
Princess Eugenie and Jack's new little bundle of joy is the eleventh-in-line to the throne, which means that Eugenie's uncle Prince Edward will move down to twelfth place.
However, it's unlikely that Eugenie and Jack's baby will have a royal title, as their children will take their rank from their father.
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