The news that Boris Johnson’s partner, Carrie Symonds, is pregnant has been Westminster’s worst kept secret for some weeks.

Symonds had not been seen in public since election night. The pair then took a highly private 12-day break on the Caribbean island of Mustique just after Christmas, and subsequently disappeared together to Chequers for another 10-day break at half term.

As speculation grew among MPs and political commentators, the rumours of Symonds’s pregnancy began to emerge publicly on the Guido Fawkes blog and from the PoliticalPics Twitter account of one of the photographers who works outside No 10.

And now Johnson has confirmed the news through a brief statement saying the couple are engaged and their baby is expected in early summer.

The congratulations poured in but the announcement comes at a particularly tricky time for Johnson’s government as it feels the heat over its handling of coronavirus, with its home secretary at war with her top civil servant, and flooding devastating parts of England.

Having spent so much time away from Downing Street in recent weeks, Johnson has been accused by the opposition of being a “part-time prime minister” whose mind is not focused on the job.

Johnson has fought back against that charge, saying he runs a cabinet with other ministers more than capable of leading responses to big events in their portfolios, such as the flooding.

However, there have been growing rumblings among Johnson’s Tory colleagues that they feel he has been distracted in recent weeks and would like to see him more visibly engaged with running the country.

Any developments in Johnson’s private life also carry something of a risk for the prime minister. Inevitably, it turns attention on to his chequered history of relationships, and repeated refusal to say how many children he has.

The prime minister’s divorce from his second wife, Marina Wheeler, is not yet finalised, and his third marriage to Symonds will be the first wedding of a sitting prime minister in 200 years.

Yet some of Johnson’s supporters believe the news of a new arrival in Downing Street could provide a “baby bounce” of good cheer for the country – at a time of uncertainty and anxiety over coronavirus in particular.

And in the short term at least, the announcement will have the effect – intended or not – of taking up column inches in the Sunday newspapers that might otherwise be devoted to the government’s difficulties.