But what's the secret to her color? Redken Shade EQ gloss. Yes, because of Stone's light natural hair color, Cunningham reaches for gloss instead of hair dye. "That color gloss is amazing because it feels like a conditioner, but it actually stains the hair," Cunningham revealed to Refinery29. "It's not a real color dye, but because it's acid-based, it lays so nicely on the hair, giving it that shine," she continued.

As colorist Lucille Javier of New York's Sally Hershberger Salon explained to ELLE, using gloss instead of hair dye is quite common. "If you don't have much grey, there are ways to blend in your color," Javier explained. "Blondes can definitely get away with glossing your hair different tones, even if it's just your ends. Also, if you hair is light enough, you can just deposit tone on the hair." We know what we're asking for next time we're in the salon!