My phone booth and Dyson's battery pack are comparable memes. Both are involuntary responses to racial identity that are passed down without comment or critique. We just do it.

Black men and women alike are changed by the "battery pack," but black women go into the telephone booth alone, like a butterfly in a cocoon. But instead of coming out lighter, we more often than not emerge weighted down. And it's that moment of transformation that fascinates me. When do black girls go from being blank slates to the bathroom walls, graffitied with everyone else's slander?

Take my goddaughters. At 10 and 7, they are little girls in the most literal sense. They like playing pretend, playing in my hair and playing with my iPad. Last summer on an especially hot day, they noticed a box of hot cocoa on my kitchen counter and begged for some. When I suggested that it wasn't the right time of year for a steaming mug of anything, they protested in perfect unison, "It's always time for hot chocolate!" And I carried the hope in that sentence with me for weeks.

I don't want them to change, but I see it happening. At 7 years old, Anna, the youngest, still loves a good secret. She still wants to cut into every conversation I have with her mom, vying for my attention and begging me to look at her "doing stuff." We had tea after the ballet a few weeks ago, and Anna declared it "a girl's night out!" It was three in the afternoon.

Nancy, 10, is already sort of over it. She sits up straight without being asked and is content to eavesdrop on an adult conversation, nodding in agreement to punch lines she can't have understood. Her schooled nonchalance is almost unnerving. More than just maturing like any other little girl, Nancy is dumping her naiveté as if it's nuclear. I look at her and think, when did this happen?

That's the question, among others, I plan to ask every woman I interview for a new book I'm working on. When did it happen? When did you disappear into the phone booth? When did you go from just being a girl to being a black girl? Was the transition painless? And do you miss it -- the levity other girls-cum-women get to slip into that we seem to be barred from?

When did you stop being like Gabby Douglas?

"I have an advantage because I'm the underdog and I'm black and no one thinks I'd ever win," she told the New York Times last week. "Well, I'm going to inspire so many people. Everybody will be talking about, how did she come up so fast? But I'm ready to shine."

The shine part Gabby has down, and that's what I'm hoping rubs off on the rest of us.

Helena Andrews is a contributing editor at The Root and author of Bitch Is the New Black, a memoir in essays. Follow her on Twitter. 

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