The name Gwen Stefani is practically synonymous with “platinum blonde.” With very few exceptions — like baby blue and pink hair moments in the late ‘90s and black dip-dyed ends in 2014 — the singer has always been a flaxen icon. We honestly can’t even remember when she’s let even a centimeter of her roots show, so it’s easy to forget that she’s naturally a brunette. Luckily, she reminds us of her natural hair color every now and then, like in the throwback photo she posted to Instagram for her brother’s birthday.On Wednesday, June 17, Stefani posted, “Happy b day @ericstefanimation #ericstefani i wouldn’t be me w out u! love u!!!” alongside a photo of herself presenting her older brother and former bandmate, Eric Stefani, with a birthday cake. Based on the quality of the photo and the style of the clothing, it seems to have been taken in the early 1990s. But the real giveaway regarding how old the photo may be is Stefani’s hair color.Stefani, seen wearing a white, sleeveless dress, is a brunette in the picture. Though it’s a paler shade of brown — one might even call it bronde — it’s a dramatically different look than how we typically picture the No Doubt frontwoman. There are hints of blonde highlights (she’s a California girl, after all), foreshadowing the lighter look Stefani would soon switch to.This isn’t the first time Stefani has given us a look at her childhood hair color. Last June, for Father’s Day, she posted a family photo revealing a rich brown shade. And in her iconic “Cool” video, she wore a brunette wig reminiscent of her natural color.Stefani hasn’t let the lockdown stand between her and her signature blonde style, but if she ever wanted to give bleach a break, she can feel confident that she’d look just as awesome as a brunette.More on celebrity hair color:Now check out 100 years of hair color:Follow Marci on Instagram and Twitter, or subscribe to Allure’s newsletter for daily beauty stories delivered right to your inbox.