"All girls are princesses, and today, I feel beautiful inside and out," she wrote.
Cancer may have robbed this Texas teen of her hair, but not her confidence.
When Andrea Sierra Salazar, 17, was diagnosed with Hodgkin's lymphoma in February, her sister Sofia, 15, told InsideEdition.com, "We were all kind of freaked out. We didn't know what we were going to do. This is all new for us."
Andrea soon began treatment for the cancer, but said that as she started losing her hair, she started losing self-esteem.
"I would look at myself in the mirror, and think that's not really how I see myself," she said.
"I was right there next to her when she came out of the shower," Sofia said, "and all of her hair was in a ball. She was brushing the couple hairs that were left [on her head]. It was really sad."
Like many other women battling cancer, Andrea told InsideEdition.com she took to wearing a wig to avoid being treated differently, though it was uncomfortable: "I felt obligated to wear it out."
To take her mind off the painful treatments, her mom suggested she revisit modeling — something she had always loved, but never had time for.
"Chemotherapy was pretty hard but between each session, modeling has helped me so much to look forward to the next day," Andrea said.
Eventually, during a shoot with photographer Gerardo Garmendia, she decided to take off her wig.
"I wanted to give off the message that hair doesn't define you," she said. "I [felt] like a princess before, why shouldn't I now? Cancer shouldn't stop you from feeling like a princess."
Cancer doesn't stop me me from being a princess. ? pic.twitter.com/39RaDuVwkH
— Andrea Sierra (@sierraandrea99) August 10, 2016
She even posted the photo series to her Facebook, captioned: "All girls are princesses, and today, I feel beautiful inside and out."
Her younger sister told InsideEdition.com, "She's always had that spark. She found that instinct and put herself out there. It was a natural ability."
Andrea said she will undergo her final round of treatment Tuesday afternoon, and despite chemotherapy's effects, she wrote on Facebook: "This journey has taught me to love and accept myself regardless of the way I look."
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