Here is the timeline for the Duke and Duchess of Cambridge’s third baby:
September 4 2017 – Kensington Palace announces that William and Kate are expecting their third child.
The duchess, who is suffering from severe morning sickness known as hyperemesis gravidarum, pulls out of a planned appearance at the Hornsey Road Children’s Centre in London.
September 5 – At his first public appearance since it was disclosed he was to become a father again, William says, at the National Mental Health and Policing Conference in Oxford: “It’s very good news”, but admits the family is not getting much sleep.
September 7 – Prince George starts school – but Kate is too poorly to accompany him to the school gates so William takes the young prince on his first day.
September 14 – William says Kate is doing “very well”, when he visits Aintree University Hospital in Liverpool.
September 18 – The duchess appears in a video message, backing the You’re Never Too Young To Talk Mental Health campaign run by the Anna Freud National Centre for Children and Families.
October 10 – Kate, showing a slight baby bump, makes her first public appearance since her pregnancy was announced as she attends a Buckingham Palace reception honouring mental health campaigners.
October 16 – Kate makes a surprise appearance at Paddington station, joining William and Prince Harry at a charity event, where she dances on the platform with Paddington Bear.
October 17– William and Kate reveal their baby is due in April. BBC newsreader Simon McCoy reacts by declaring on air: “Clear your diaries. Get the time booked off, ‘cos that’s what I’m doing.”
The Palace also announces William is to make a solo trip to Finland. A visit to Sweden and Norway by the duke and duchess is shifted to January to ensure Kate is well enough to attend, it is thought.
October 18 – Kate makes another surprise visit when she turns up at West Ham’s London Stadium for a Coach Core event with William and Harry.
October 31 – Kate steps out in sports gear for a visit to the National Tennis Centre.
November 7 – The duchess, in a black floor-length dress by Diane von Furstenberg, attends an Anna Freud National Centre for Children and Families gala in Kensington Palace’s 18th century Orangery.
November 8 – Kate addresses a Place2Be mental health forum and stresses that getting help and support for young children at the very earliest stage helps improve their outcomes later in life.
November 12 – Kate joins other royals to watch the Remembrance Day service from a balcony overlooking the Cenotaph in Whitehall, central London. The night before, the duchess attended the Festival of Remembrance at the Royal Albert Hall.
November 14 – The duchess tells a single father during a visit to the Hornsey Road Children’s Centre in north London that William initially found it difficult adjusting to parenthood.
November 20 – William, Kate and the rest of the royal family celebrate the Queen and Duke of Edinburgh’s platinum wedding anniversary at a special party in Windsor Castle.
November 22 – The duke and duchess visit Solihull where Kate takes part in an off-road Land Rover driving experience not recommended for pregnant women.
November 24 – William, in black tie, and four months pregnant Kate, wearing a sequinned cornflower-blue Jenny Packham gown, attend the Royal Variety Performance, but their arrival is delayed by an hour after an incident nearby which saw armed police rush to London’s Oxford Street.
November 28 – Kate congratulates Prince Harry and Meghan Markle on their engagement.
November 29 – William makes a solo visit to Finland, celebrating the centenary of the country’s independence.
Kate visits Robin Hood Primary School in south-west London to see its work with the Royal Horticultural Society’s campaign for school gardening.
She tells pupils she has “fond memories” of being outdoors as a child and is passing that passion on to her own children.
December 12 – The duchess hears stories of mothers caught up in the Grenfell Tower blaze as she visits the Rugby Portobello Trust centre which is supporting the local community.
William and Kate receive Gold Blue Peter badges from the CBBC children’s show for their work around mental health issues affecting children.
December 14 – William and Kate join victims of the Grenfell Tower fire at a memorial service in St Paul’s Cathedral.
December 25 – The couple join Prince Harry, Meghan Markle and other members of the royal family at church at Sandringham on Christmas Day.
January 8 2018 – Two-year-old Princess Charlotte starts at Willcocks Nursery School, with Kate taking the photographs released to celebrate her big day.
January 10 – The duchess speaks about the addictive nature of social media, saying it can be “hard to break away from”, as she meets teenagers at the Reach Academy Feltham in west London.
January 17 – Kate pats her bump and jokes that she is less “sporty” with two children and a third on the way, as she visits a tennis session for pupils at Bond Primary School in Mitcham.
January 23 – The duchess says she is committed to helping the “youngest and most vulnerable” in society as she launches a mental health website for teachers supporting pupils.
January 24 – Kate sympathises with the mental health plight faced by many mothers, saying how generally they are supposed to be “super happy” but one in four is not, as she meets psychiatrists, midwives and health visitors specialising in treating mothers with mental health issues.
January 30 – William and Kate pay an official visit to Sweden and Norway. Engagements amid freezing temperatures include playing an unusual form of hockey called bandy in Stockholm, and joining children round a camp fire in Oslo.
February 5 – Kate records a personal message to try to spur children on to be comfortable in their own skin as part of Children’s Mental Health Week.
February 7 – Kate, as patron of the Action on Addiction charity, opens a new community-based treatment facility in Wickford, Essex. Her heel gets stuck in a grate as she arrives.
February 18 – Kate wears dark green to the Baftas. Most nominees and other guests wear black to the awards in support of the Time’s Up campaign in the wake of the Hollywood sexual harassment scandal.
February 19 – The Duchess shows off her growing baby bump at the Commonwealth Fashion Exchange at Buckingham Palace.
February 21 – The Duke and Duchess go on an away day to Sunderland to open the music and arts hub The Fire Station and visit the new Northern Spire, bridge over the River Wear.
February 27 – The duchess hugs Professor Jacqueline Dunkley-Bent, who helped to deliver one of her children, when they are reunited during Kate’s visit to the Royal College of Obstetricians and Gynaecologists in London.
She also jokes that William is in denial about a third baby, while visiting the Snow Leopard ward at St Thomas’ Hospital, London, to launch the Nursing Now campaign.
February 28 – Kate, Meghan Markle, Harry and William appear on stage at a Royal Foundation forum – the first time the “fab four” have carried out an official engagement together.
March 6 – Kate visits Pegasus Primary School in Oxford and is given a book of lullabies to help the new baby sleep.
March 7 – Kate opens the new Place2Be headquarters in central London.
March 12 – The duke and duchess join the Queen, Prince Harry, Meghan Markle and the royal family at the Commonwealth Day service at Westminster Abbey.
March 17 – Pregnant Kate sips water, while William a pint of Guinness with the Irish Guards during the St Patrick’s Day parade in Hounslow, west London.
March 21 – Kate attends a symposium on early intervention with social and emotional support for children.
March 22 – The Duchess carries out her final engagements before going on maternity leave. She shows off her culinary skills with William and takes part in a general knowledge Commonwealth quiz.
March 26 – Kensington Palace announces that Kate has become the first royal patron of the V&A museum.
April 1 – Kate attends the Easter Sunday service at St George’s Chapel, Windsor.
April 9 – Parking restrictions and barriers are put in place outside the Lindo Wing at St Mary’s Hospital.
April 16 – William welcomes delegates to UK for the Commonwealth Heads of Government Meeting, and holds audiences and attends events throughout the week.
April 21 – William and the rest of the royal family – minus Kate – celebrate the the Queen’s 92nd birthday at a concert at the Royal Albert Hall in London.
April 23 – Kate is admitted to the Lindo wing at St Mary’s in Paddington in the early stages of labour.