The 31-year-old Duchess of Cambridge showed off some grey hairs during a public appearance with Prince William in London last week.
While we originally thought maybe the greys were due to the stress of caring for a newborn, it seems Kate's always had some greys, which she previously hid with hair dye.
The Daily Mail reports that she's been dying her hair since before her pregnancy, but may have stopped now because she's breastfeeding.
Although studies have said it's "very unlikely a significant amount of the chemicals used in hair dyes will be passed on," it seems Kate's playing it safe and opting to let her hair go natural for now.
We still think she looks great!