Boris Johnson’s wife Carrie has given birth to her second child with the Prime Minister.
It follows after a tumultuous 24 hours for Downing Street.
Mr and Mrs Johnson announced the birth of a "healthy baby girl" at a London hospital earlier on Thursday 9 December.
It is understood the Prime Minister was present throughout the birth.
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A spokeswoman for the couple said: "Both mother and daughter are doing very well. The couple would like to thank the brilliant NHS maternity team for all their care and support."
Birth came morning after Plan B announcement
The couple announced they were expecting their second child at the end of July, as the 33-year-old environmental campaigner spoke of having a miscarriage earlier this year.
The birth of a sister for Wilfred came the morning after the Prime Minister announced England is entering Plan B to combat the spread of the Omicron variant of coronavirus.
Also on Thursday morning, the Conservatives were fined £17,800 over the controversial donation to help cover the lavish refurbishments to the couple's Downing Street flat.
As well as facing Tory anger over the latest restrictions, Mr Johnson is also facing the fallout of an allegedly rule-breaking Number 10 Christmas Party last year on 18 December, which forced the resignation of senior government aide Allegra Stratton.
The new arrival now means the Prime Minister has at least seven children, although he frequently obfuscates when asked how many.