Buckingham Palace announced today (17 January) that Zara had given birth to a 7lbs 12oz baby girl at Gloucestershire Royal Hospital. No name has been revealed yet.
Proud new dad Mike, who was with Zara during the birth, took to Twitter this afternoon to say becoming a father was the "best" moment of his life.
"Thanks so much for all your kind messages. Definitely the best day of my life today, so happy! The girls are both doing great!" he tweeted.
"Βig thanks to all involved at Gloucester Royal, they were fantastic! #newglawsfamilymember."
Buckingham Palace announced the royal birth in a statement, saying The Queen, The Duke of Edinburgh and both Zara and Mike's parents were "delighted" with the news.
Following in Zara's footsteps, the baby will not have a royal title and will instead be known as Miss Tindall. She is 16th in line to the throne.
Zara and Mike announced their pregnancy in July 2013. They met in 2003 during England's Rugby World Cup campaign and married eight years later in Canongate Kirk, Edinburgh.
Congratulations to Zara and Mike!
Stars who have announced pregnancies in 2014 in pictures:
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