Clare Bowen is changing up her look for a powerful cause.

The Nashville star looks stunning in a new photo shared on her Facebook page, trading in her lengthy blonde locks for a brand new pixie cut. "It's just hair," a tagline on the photo reads.

In her caption, the Australian actress opens up about her own heart-wrenching battle with childhood cancer. Bowen says she was diagnosed with end stage nephroblastoma at four years old and that her family was told "the only hope of saving me, was an experimental treatment that might kill me anyway. But without it I had maybe two weeks left."

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Without detailing her treatment, Bowen says that she lost her hair during that time. "I got to grow up surrounded by children just like me," she wrote. "We were mostly bald, all tubed, taped, bandaged up and stitched back together. We were all missing parts, some obvious like eyes or legs, others more hidden, like lungs and kidneys. Those who still could, tip-toed around like little fairies because chemotherapy had destroyed the muscles in our legs and it hurt to put our heels on the floor. But we were all together, so no one's appearance came into question. No one got laughed at or teased. We were all we knew."

You can read Bowen's full story in the post below.

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Bowen says she was inspired to share her memories -- and cut her hair -- after she heard about "a little girl who said she couldn't be a princess because she didn't have long hair."

"I wanted her, and others like her to know that's not what makes a princess, or a warrior, or a superhero," Bowen continued. "It's not what makes you beautiful either. It's your insides that count... even if you happen to be missing half of them."

Bowen plays fictional country songstress Scarlett O'Connor on Nashville, now in its fourth season on ABC.

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Earlier this season, the soapy drama featured a special guest appearance from Steven Tyler. But before the show hit the air, the Aerosmith frontman opened up to ET about struggling to learn his lines. See the interview below.