Boris Johnson and Carrie Symonds have revealed the name of their baby boy.
The Prime Minister’s latest son is called Wilfred Lawrie Nicholas Johnson.
The newborn has been named after Dr Nick Price and Dr Nick Hart, doctors that cared for Mr Johnson while he was recovering from the coronavirus.
A post on Ms Symonds Instagram page read: “Introducing Wilfred Lawrie Nicholas Johnson born on 29.04.20 at 9am.
“Wilfred after Boris’ grandfather. Lawrie after my grandfather.
“Nicholas after Dr Nick Price and Dr Nick Hart – the two doctors that saved Boris’ life last month.
“Thank you so, so much to the incredible NHS maternity team at UCLH that looked after us so well.
“I couldn’t be happier. My heart is full.”
The engaged couple welcomed their first child together on Wednesday morning when the newborn apparently arrived weeks earlier than expected.
Ms Symonds, 32, had previously said that the baby was due in the early summer, leading to the belief that the due date was in June.
A spokeswoman for the couple said the “healthy” baby boy was born at an NHS hospital in London. Both mother and baby were said to be “doing very well”.
Facing the worst health crisis for a century, the twice-divorced Prime Minister, who has fathered six children with three women, will take a “short period” of paternity leave later in the year.
New fathers are entitled to up to two weeks of statutory paternity leave.
It must end within 56 days, or eight weeks, of the birth, a period that would take Mr Johnson to the last week of June.
As for baby names, Wilfred, Alexander, Winston, Thomas and George were among the bookies’ favourites.
Mr Johnson was present for his third son’s birth, but returned to work in Downing Street shortly afterwards to lead the Government’s efforts against coronavirus.
The new family are planning to live in their Downing Street flat along with their dog Dilyn, a No10 spokesman confirmed.
The Queen was among the many to send messages of good wishes to the couple.
Mr Johnson has relied on the NHS during the Covid-19 crisis through his own battle with the new strain of coronavirus and the birth of his child.
He returned to full-time work on Monday, two weeks after he was released from St Thomas’ Hospital, where he was moved to intensive care while gravely ill with the virus.
Ms Symonds, an environmental campaigner and public relations expert, also had symptoms of Covid-19.
The couple has been living together in Downing Street since Mr Johnson became Prime Minister in July last year.
In February, they announced that they were expecting their first child and they were engaged to be married.
Mr Johnson has at least six children, possibly seven.
He has refused to confirm how many children he has fathered.
He was previously married to lawyer Marina Wheeler for 25 years. They had four children together – Lara Lettice, Theodore Apollo, Cassia Peaches and Milo Arthur Johnson.
Mr Johnson and Ms Wheeler announced in September 2018 that they had split and they divorced this year.
His fifth child – Stephanie – was born in 2009 after an affair with art consultant Helen Macintyre.
In 2013, the Court of Appeal rules that the public had a right to know that he had fathered a daughter during an affair while he was London’s mayor.
Documents from those proceedings alleged that Stephanie Macintyre was one of two children Mr Johnson had fathered as a result of an affair.
The Prime Minister has refused to confirm how many children he has had.
He was asked a number of times during last year’s general election campaign.
Mr Johnson and Ms Symonds made history as the first unmarried couple to officially live together in Downing Street when they moved in last summer, after he won the Conservative Party leadership contest.
The new arrival is the third baby born to a serving prime minister in recent history.
Tony Blair’s wife Cherie gave birth to son Leo in May 2000, three years after her husband’s first election victory, and David Cameron and wife Samantha welcomed daughter Florence in 2010.
The last babies born to prime ministers before Leo and Florence arrived more than 150 years ago.