This teen shaved his head to match his sister's 10-inch brain surgery scar

No sibling rivalry here.

A 19-year-old man from Mississippi is using a haircut to show support for his younger sister as she undergoes treatment for a tumor, Inside Edition reports.

After weeks of nausea and hearing loss in her left ear, 17-year-old Alana McMullan was diagnosed last month with a medulloblastoma tumor. She had to undergo an operation on her brain, which left her with a 10-inch scar.

Determined to not let her “fight alone,” her older brother, Ethan McMullan, contacted his barber and arranged to have a design mimicking the scar — which resembles the numeral seven — shaved into his hair.

“I saw her scar right after she got out of surgery,” Ethan said. “I saw it before she did. I was like ‘that’s a pretty big scar,’ and I was like, ‘I think my barber can do something that will look like that.’”

“I thought it was pretty cool,” Alana told People of the gesture. “I didn’t know he was going to do it so soon. I thought he was going to wait a little while. I hadn’t even seen my scar until he sent me that picture.”

The siblings will continue to have matching hairstyles as the medical battle continues. Doctors have identified the tumor as malignant, and Alana will soon begin chemotherapy.

Should her hair fall out as a result the the treatment, Ethan has vowed to shave his head in solidarity.

Read more from Yahoo Lifestyle:

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‘This Is Us’ shows why brother-sister relationships are so powerful

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