Kate Middleton went under-the-radar to secretly work at a busy maternity ward in London this week.

The Duchess of Cambridge secretly worked for two days with Kingston Hospital Maternity Unit in London. The busy maternity ward delivered more than 5,900 babies in 2018, and also offered assistance with home births. The maternity ward also celebrated its midwife-led unit Malden Suite's 10th anniversary this year, reports Mail Online.

The mother-of-three has often expressed interest in early years development and child mental health in the course of her royal work, but the purpose of her working at the facility has not been revealed yet.

According to The Sun, Kate Middleton during her short work at the maternity ward on Tuesday and Wednesday learned more about its work as part of her "Early Years" project, an initiative that aims to look at how experiences between birth and five years affect one as adults.

The 37-year-old is also Royal Patron of East Anglia's Children's Hospices (EACH) and opened a £10 million Nook children's hospice in Norfolk earlier this month. The royal also visited the charity's new hospice in Framingham Earl and interacted with children and families being supported by EACH.

One such interaction that made headlines was her conversation with Betsy Fletcher, a girl whose 10-year-old brother has dystonic cerebral palsy and other complex medical needs. Kate told Betsy: "I love your plaits. My daughter Charlotte loves plaits too but her hair is only this long so we have to do them up at the side."

kate middleton
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Meanwhile, reports have emerged that the Duke and the Duchess of Cambridge have decided to open a part of Kensington Palace for school kids to learn about the royal family. A two-storey education centre will be reportedly constructed at Kensington Palace. It will be an extension to Grade I-listed Queen Anne's Orangery and a new garden will link the 323-year-old building to the royal couple's West London home, reports The Sun.

Prince William and Kate's own children, Prince George, six, Princess Charlotte, four, and one-year-old Prince Louis, were delivered at the Lindo Wing at St Mary's Hospital.