She turned the entire third floor into a dream nursery for her sons.

Princess Diana called several grand houses and palaces home in her lifetime, but it was her Kensington Palace home that she truly made her own.
A newlywed Diana and Prince Charles (now King Charles III) moved into Apartments 8 and 9 in 1981. While the combined apartments have since been separated back into two dwellings, when joined, they offered more than enough space for the royal couple and their growing family. Diana turned the entire third story into a nursery for sons Prince William and Prince Harry, whom she welcomed in 1982 and 1984, respectively.
Just 20 years old when she came to live at the palace, Diana already had a burgeoning interest in design. This interest was famously reflected in her bold fashion choices, but it also manifested in her decorating. She and interior designer Dudley Poplak renovated Apartments 8 and 9 together, adding details that would fill many a ‘dream home’ Pinterest board today: strawberry-print carpet, cornflower blue curtains with white ruffle trim, bamboo dining chairs, a candy pink sofa. Each detail represented the young princess’s developing aesthetic—one that was vibrant, feminine, and fun.
Having put her personal touch on the place and made fond memories there with her sons, Diana continued to reside at Apartments 8 and 9 until her death in 1997. It was subsequently left empty for ten years before being renovated in 2008, per The Guardian.
Here’s everything to know about Princess Diana’s Kensington Palace home, Apartments 8 and 9, where she raised William and Harry—and let her design talents shine.
The apartments date back to the Georgian era.

Although public records of the expansion of Kensington Palace are scarce, some sources suggest King George I added the apartment which would become the future home of Diana and Charles. George built it in the early 18th century, the story goes, to accommodate his mistress, Melusine von der Schulenburg, Duchess of Kendal. It was part of a larger effort on his behalf to win over his staff and peers as an “imported” king, historian Lucy Worsley explained in an episode of Lucy Worsley’s Royal Palace Secrets. “He [George I] turned this place into a party palace,” she said.