Kate had first been seen with the brighter shade in August, shortly after returning from a summer holiday in Greece with Prince William and their children — Prince George, Princess Charlotte, and Prince Louis.
The family had been sailing near the island of Kefalonia, a sunny destination often referred to as the “St. Tropez of Greece.”
Experts weigh in on the change
Not everyone is convinced that sunshine alone explains the transformation.
Creative color expert Seung Ki Baek told the Daily Mail:
“Lightening the hair in the sun can occur over time, but the effect is often less dramatic than for those with a naturally lighter base.”
In other words, while sun exposure can lighten hair, the result may not be quite so noticeable without some additional help.
Celebrity stylist Sarah Gadston suggested that the holiday could still have contributed to the change.
“After a sun-soaked holiday in Greece, Kate returned not only with a refreshed spirit but also with naturally lightened hair,” Gadston said.
“The combination of sea air, sunshine, and saltwater had gently lifted her hair to a softer shade—creating the perfect starting point for her next salon visit.”