In an Instagram post accompanied by a picture of Ms Johnson holding hands with the couple’s first two children, the 35-year-old wrote:
“New team member arriving in just a few weeks. I’ve felt pretty exhausted for much of the last 8 months but we can’t wait to meet this little one.
“Wilf is v excited about being a big brother again and has been chattering about it nonstop. Don’t think Romy has a clue what’s coming…she soon will!”
The former prime minister, 58, and his wife had their first son together, Wilfred, in April 2020. Their second child, daughter Romy, was born in December 2021.
Earlier that year, Ms Johnson revealed that she had suffered a miscarriage which had left her “heartbroken”. Upon her birth, Romy was labelled a “rainbow baby” by the couple, a term used to refer to a child born after the loss of a baby to miscarriage, stillbirth or neonatal birth.
A British media consultant, Ms Johnson worked as a media official for the Conservative Party. She is a senior adviser to Oceana, an ocean conservation charity.
Opening up about her miscarriage, Ms Johnson said she had found comfort in speaking to others who had also experienced a similar loss.
The timing of her announcement suggests she was pregnant at the time of their wedding.
The couple were engaged in late 2019 and they married in an intimate wedding ceremony at Westminster Cathedral in May 2021.
While the baby girl was Ms Johnson’s second child, Mr Johnson is more familiar with the experience of parenthood. During his resignation speech, Boris thanked Carrie and “all of my children”, however, the exact number of offspring the former prime minister has remains unclear.
It is believed that he has eight children, however, he has not officially confirmed the exact number.
What is known is that Mr Johnson and his second wife, Marina Wheeler, who separated in 2018, have four children together: Lara Lettice, 27, Milo Arthur, 25, Cassia Peaches, 23, and Theodore Apollo, 21.
Mr Johnson also has a fifth child, Stephanie Macintyre, who was fathered as a result of an affair with art consultant Helen Macintyre.
The Appeal Court ruled in 2013 that the public had a right to know that he had fathered a daughter during an adulterous liaison while mayor of London in 2009.
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