The Duke and Duchess of Cambridge have thanked the public for their "warm wishes" ahead of the birth of their second child - but they still do not know if it will be a boy or girl.
A heavily pregnant Kate is expected to give birth towards the end of April and for the delivery will return to the Lindo Wing, the private maternity department of St Mary's Hospital in Paddington where Prince George was born.
William will take two weeks paternity leave from his job as an air ambulance helicopter pilot and join his family at Kensington Palace where they will spend the first few days after the birth before travelling to their Norkfolk home Anmer Hall, a source has said.
The Duke is due to begin flying rescue missions with the East Anglian Air Ambulance in the summer but at the moment is working from three bases undergoing training.
The source said: "The Duke and Duchess are hugely grateful for the warm wishes they have received from people throughout the UK and indeed around the world and over the last few months.
"They know that people are excited that Prince George will soon have a little brother or sister, it means a great deal to them that so many will be celebrating this important moment for their family."
The source confirmed that the sex of the baby will be a surprise to the couple who do not appear to have asked about their baby's gender during routine scans.
The delivery team will be led by Guy Thorpe-Beeston, s urgeon gynaecologist to the Royal Household, who is a consultant obstetrician and gynaecologist at the Chelsea and Westminster Hospital.
The birth of the child will be announced on the official Kensington Palace Twitter account and also in the traditional manner - with a royal bulletin displayed in Buckingham Palace's forecourt on the same ornate easel used when George was born.
But the news of a new prince or princess is unlikely to be announced overnight as the Queen and members of both families will have to be informed first.
The Duke and Duchess have a live-in Spanish nanny, Maria Teresa Turrion Borrallo, to help with childcare and it is understood they have no plans to hire more staff to help with looking after their family.
The source would not comment on when Kate would return to public duties but added "as you would expect, with two very young children her focus will be on the family during the summer".