Carrie Johnson has announced that she is expecting her second child with husband Boris by sharing the news in an emotional post on social media.
The 33-year-old, who is mum to one-year-old Wilfred, said that she and the Prime Minister are expecting another new arrival in December, while also revealing her "heartbreak" at suffering a miscarriage earlier in the year.
She wrote on Instagram : "Hoping for our rainbow baby this Christmas. At the beginning of the year, I had a miscarriage which left me heartbroken. I feel incredibly blessed to be pregnant again but I've also felt like a bag of nerves."
The term 'rainbow baby' is used for parents expecting a child after losing a baby to miscarriage, stillbirth or neonatal death, and was coined to signify the arrival of something beautiful after a storm.
Jennifer Kulp-Makarov, a Reproductive Endocrinology and Infertility Specialist, explained to Parents : "It is called a rainbow baby because it is like a rainbow after a storm; something beautiful after something scary and dark.
"It is an extremely emotional and devastating experience to lose a pregnancy [or baby]. To create a life or bring a baby into the world after such a loss is amazing like a miracle for these parents."
In her Instagram post, Carrie went on to say: "Fertility issues can be really hard for many people, particularly when on platforms like Instagram it can look like everything is only ever going well.
"I found it a real comfort to hear from people who had also experience loss so I hope that in some small way sharing this might help others, too."
The couple welcomed son Wilfred in April 2020, not long after Mr Johnson, 57, was released from intensive care where he had been treated for Covid-19.
In May of this year, Mr Johnson married Carrie in a secretly-planned ceremony in Westminster, making him the first Prime Minister to marry while in office for two centuries.