Sydney Sikes slurps down the last of her Capri Sun juice pouch, and in that moment, I am reminded that just two months earlier, she turned 15.

If you watch Sikes in the makeup tutorial videos she posts on Instagram under the name “SydMarie” — some of which have drawn tens of thousands of views — it’s easy to forget or even doubt her age. She moves with an easy confidence, and when her face is highlighted and contoured to her satisfaction, she could easily pass for 25.

But if you could see beyond what those videos show, if that tiny camera on her iPhone could pan out and around her as she sweeps sunset shades across her lids, you would see glimpses of her teenage life in Northern Virginia. You would see she is sitting in a bedroom decorated with hot pink and black wall hangings. You would see a picture on her desk that shows her on a cheerleading team and a full-length mirror that holds a white sash that reads, “Homecoming Court.”

You would see a girl who, in the middle of filming one recent afternoon, calls out to her father:

“Hey, Dad, can you do me a favor? Bring me a Lunchables?”

He brings the juice pouch with it. Sikes snacks and drinks, stopping occasionally to talk, while spending two hours doing her makeup for a video that she will edit down to about a minute and then post for her 31.9k Instagram followers to see.

If you have ever wondered how a person becomes an “influencer,” that modern-day title reserved for those who have become so popular on social media that people want to buy what they buy and do what they do, Sikes can tell you.

In just two years, she went from a girl who started experimenting with makeup because she felt insecure about her cystic acne to a makeup artist with an enviable résumé.

She is sponsored by several cosmetic brands, her name and face have appeared on a limited-edition makeup collection, and people pay her to make them look beautiful on days when they need to look their best. She has done makeup for three brides. She has worked at a fashion show. And among her repeat customers is fitness coach Brooklyn Hillenbrand, who is also an influencer with 279k Instagram followers. Sikes has done her makeup for body building competitions.

“I’ve actually had to turn down a lot of work in the last few months,” Sikes tells me as I watch her complete a look using eye shadow from ColourPop, one of the brands that sponsors her. That means the company sends her free makeup and she agrees to use it on camera a set number of times, she explains.

As we talk, I confess to her that I started wearing makeup at 13, too, for the same reason she did: my own insecurities. I got chickenpox that year and couldn’t stand the thought of returning to school before the scars faded.

Unfortunately, unlike her, I had no skills. Back then, I used CoverGirl foundation in a shade that didn’t match my skin, making my face look like it belonged to a different person than my neck.

Sikes says she cringes, too, when she looks back at her work at 13 (which, yes, was only two years ago).

In those early images on her Instagram account, most people would see a stunning girl. She sees how much she hadn’t yet learned.

She refuses to delete them, though, because they show others “you can do it,” she says.

“I get messages all the time from people that are like, ‘I could never do that,’ ” she says. “I worked really hard for what I can do now, and there is a lot of learning that goes on behind it.”

She also hears from people who assume her parents are rich. She tells them they aren’t. Her father works in government contracting, and her mother is a stay-at-home parent.

Sikes started learning about makeup by buying inexpensive brands with money she earned from walking dogs.

“Sydneyfuntime Dog Walking Service!!” reads the flier she made when she started the business just before she turned 11. It lists her parents’ names and this pitch: “If you are in the middle of a situation, tired, or if you want to have a relaxing day that’s where I come in to help! Call me and I will walk your dog for 30 minutes for $5.00.”

Her mother, Amy Sikes, knows what you’re probably thinking. She thought it, too. When her daughter first came to her, asking whether she could start using makeup and posting the looks on social media, she was hesitant to give her permission. She worried she was too young. She also feared she was doing it for the wrong reason.

“I thought it was about vanity,” she says. “But for her, it’s an art.”

She had noticed how at 4, her daughter could look at a drawing and re-create it, and how at 8, she transformed a pair of white sneakers into two impressive, very yellow Minions.

Now, she marvels at how her daughter uses her face as a canvas. The rising 10th-grader takes medication to keep her acne under control, and when she is not filming, she rarely wears makeup. But when she is sitting in front of that camera, she can spend between one to six hours creating looks that range from prom appropriate to elaborately eerie. She once transformed her face into a Ouija board.

“At first, when she started the account, I didn’t see what she saw,” Amy Sikes says. “Now, I really believe she’ll make it in this industry.”

On her daughter’s desk sits a magazine signed by Beyoncé’s renowned makeup artist Sir John. Amy Sikes was there when her daughter met him at an event this summer. She recalls how he held up the makeup palette the teenager created for the cosmetic company Inglot USA and said, “Everyone, this girl is 14. She is going to be big.”

Sydney smiles as she listens to her mom recount that moment. In one of her posts, she describes her mom as her “biggest support.”

“I may be extremely young but she helps me understand age is just a number & with passion & drive I can accomplish whatever I set my mind to,” it reads. “She is crushing it because she is raising me to be a woman of strength & she uplifts everyone she knows & would give the world to someone in need.”

Her mom keeps the passwords to all her online accounts and monitors them for any concerning activity. When negative comments pop up, they often bother her more than they do the teenager, who laughs off many and tries to respond positively to even the biting ones. When someone told her she resembled “Shrek,” the green cartoon ogre, she jokingly told them to get out of her swamp.

“I think the biggest hurdle that she overcame, or I overcame, was the negativity in the beginning by the parents,” Amy Sikes says of some Northern Virginia parents who didn’t approve of what her daughter was doing. She says they spoke about her behind her back and chastised her online. “She had never had a boyfriend, and they called her a slut.”

Sydney agrees that was the hardest part. She may appear more mature in the videos, but after she is done taping each look, she washes her face, and the teenager her classmates see most days appears.

Some of her teachers have commented that she lives a dual life, and she recognizes that in many ways, they’re right. She is at once an influencer with big goals and a high-schooler who is worried about upcoming cheer tryouts.

She is at once an artist who wants to make sure her eyes look just right and a girl who is thinking about her friends.

“If my friends join, can you tell me?” she asks her mom as she taps on her phone and starts an Instagram live video. Suddenly, 64 people are watching “SydMarie” do her makeup and typing messages to her. Her mom reads one after another aloud.

You look so pretty.

Love this look.

I wish I could do makeup like you.

I need you to do my makeup for prom and graduation.

How old are you?

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