Kate and Prince William sparked a false royal baby birth alarm after they drove from her parents' house in rural Berkshire in a convoy, which included protection vehicles to their Kensington Palace home.
It is only five minutes' drive from her chosen maternity unit at St Mary's Hospital, Paddington, the Daily Express reported.
According to royal sources, Kate, 31, remained in a relaxed mood after spending much of the last week cocooned with Prince William at her parents' 5 million-pound Georgian manor house in Bucklebury.
A visible police presence in the village suggested the couple were heading back to the house, on Friday.
The Duchess of Cambridge has no pressure to show off the baby to the current monarch before Kate's parents see the child.
The sources remained confident that the baby will be there in time for the Queen to get her wish and see her new great-grandchild before she leaves for Balmoral on Friday.
