When the news broke that Carrie Symonds and Boris Johnson were expecting a child, some dubbed it the “Brexit baby”.

It was seen as a personal new beginning for the Prime Minister, with the baby expected to arrive a few months after he had delivered on his political pledge to take the UK out of the European Union.

But the new arrival will instead be long linked with the coronavirus pandemic, the global event that has eclipsed Brexit in terms of magnitude and is taking a heavy toll on the UK.

The joy of having their first child together is likely to be the start of a welcome new chapter, following the PM’s close brush with death.

Three weeks before NHS staff delivered his baby, doctors and nurses at St Thomas’ Hospital in central London had seen Mr Johnson through a three-night stint in intensive care as they treated him for his coronavirus symptoms.

He later admitted his illness “could have gone either way” and individually name-checked staff who had watched over him through the night to ensure he survived.

On Wednesday, it was the couple’s turn to “thank the fantastic NHS maternity team” who delivered their first child together.

Mr Johnson had only returned to work 48 hours before the birth, having been convalescing at his country residence Chequers for two weeks following his discharge from hospital.

The PM’s close shave and new baby are among many moments the couple have occupied newspaper column inches.

They made history as the first unmarried couple to officially live together in Downing Street when they moved into the flat above Number 11, following Mr Johnson’s election as Conservative Party leader.

The 55-year-old former London mayor and the 31-year-old conservationist are now engaged, an announcement made when they revealed her pregnancy only two months ago.

Ms Symonds, a former Tory communications chief, made headlines when she was romantically linked to Mr Johnson last year, months after the announcement of his separation from second wife Marina Wheeler.

Public relations expert Ms Symonds had been in the so-called Westminster bubble for most of her career, a high point being when she was made head of party PR aged just 29.

She joined the party media machine in 2009, first as a press adviser, then head of broadcast at Conservative campaign headquarters ahead of the 2015 general election.

Her association with Mr Johnson dates back to the early years, having worked on his successful re-election bid for London mayor in 2012.

But a row that saw police called to their south London home in the early stages of the 2019 Tory leadership race offered a glimpse into the complicated private life about which Mr Johnson has tried desperately to avoid answering questions.

After moving into Number 11, they adopted a Jack Russell-cross puppy called Dilyn, which is often featured in Ms Symonds’ social media posts.

She moved out of the couple’s Downing Street apartment in March, thought to be due to coronavirus concerns, after Number 10 was turned into the Government headquarters for tackling the crisis.

She later declared that she had also shown symptoms.

When Mr Johnson was admitted to St Thomas’ Hospital to be treated for his Covid-19 symptoms, she was not permitted to visit him, meaning they did not have contact for weeks during the later stages of her pregnancy.

The couple’s new arrival is far from being Mr Johnson’s first child.

He had four children during his turbulent marriage to Ms Wheeler, which ended in September 2018 after 25 years together.

In 2004 he was sacked from the Tory front bench over a reported affair with journalist Petronella Wyatt, and the Appeal Court ruled in 2013 that the public had a right to know he had fathered a daughter during an adulterous relationship while running he was London mayor in 2009.

Claims that he squeezed the thigh of journalist Charlotte Edwardes, at a private lunch at The Spectator magazine’s HQ shortly after he became editor in 1999, overshadowed his first party conference as PM.

Allegations about his relationship with American entrepreneur Jennifer Arcuri, and whether she enjoyed preferential treatment while he was mayor, also dominated the headlines in September.

Mr Johnson has insisted Ms Edwardes’ allegations are not true and has denied any impropriety in relation to the claims about Ms Arcuri.