In a statement, the palace said: "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.
"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."
WATCH: Princess Eugenie Welcomes Baby Boy With Jack Brooksbank
The Princess shared the first image of the tot on her personal Instagram account - a sweet black and white shot of the proud parents holding their baby's fingers. She captioned it with a series of blue heart emojis.
The Prince of Wales and the Duchess of Cornwall were among the senior royals to react to Eugenie's baby news, sharing a photo from the royal wedding in 2018 on Clarence House's Instagram, and writing: "Congratulations to Her Royal Highness Princess Eugenie and Jack Brooksbank on the birth of their son."
Eugenie shared the first glimpse of her son on Instagram
A number of the Eugenie's patronages congratulated the royal on social media, including the Royal National Orthopaedic Hospital, which tweeted: "Congratulations to our Patron, HRH Princess Eugenie and Jack Brooksbank on the birth of their baby boy. We are so delighted for you both and would like to wish you all the very best."
The new mum's charity, the Anti-Slavery Collective, which she co-founded with friend Julia de Boinville, shared on Twitter: "On behalf of everyone at The Anti-Slavery Collective, we want to say congratulations to our co-founder, HRH Princess Eugenie, on the birth of her baby."
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.
Eugenie and Jack's pregnancy announcement on Instagram
The couple married at St George's Chapel in Windsor on 12 October 2018, after dating since 2010.
Here's everything you need to know about the latest addition to the royal family…
When will the royal baby's name be announced?
Royal parents usually take around two days to announce a new baby's name, with the Duke and Duchess of Sussex revealing their son Archie's name on 8 May 2019 after his birth on 6 May.
However, Prince Andrew and Sarah waited two weeks before unveiling their first child Princess Beatrice's name in August 1988, while the Queen didn't share Prince Charles' name publicly for a month after his birth in 1948.
Arthur is the bookies' favourite for the new royal baby's name with odds of 5-1, followed by James at 6-1 and then Frederick, Edward and Albert all at 8-1, while it is 10-1 for Alexander, Hugo or Alfred.
Jack and Eugenie married in October 2018
Where is the royal baby in the line of succession?
The tot is 11th-in-line to the throne after his mother Eugenie. This has also meant that the baby's great-uncle, the Earl of Wessex, has now moved down one place to 12th.
Eugenie's son will move further down the line with the arrival of new additions to the family, including when the Duke and Duchess of Cambridge's children, Prince George, Princess Charlotte and Prince Louis, grow up and have children of their own.
Will the royal baby have a title?
While Eugenie is Her Royal Highness Princess Eugenie of York, it doesn't automatically mean that her son will also inherit a title.
As things currently stand, the royal baby will not have a title because these are passed down the male line and Jack does not have a title.
However, the Queen could decide to intervene and give Eugenie's husband an earldom or issue a Letters Patent amending the rules.
When will the royal baby be christened?
Royal babies are usually christened when they are around three or four months old, although Princess Eugenie's christening did not take place until she was nine months old.
The royals at Eugenie's christening in December 1990
Eugenie was baptised at St Mary Magdalene Church in Sandringham in December 1990 and she was the first and only royal baby to date, to have a public christening.
New parents Eugenie and Jack could decide to break with tradition and follow suit with a public baptism for their first child.
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