Jameson Kessler of Shelbyville, Ind., wears a skeleton costume and calls himself "Marrow Man." He is, after all, his sister Samantha's hero.
This summer, Jameson will donate bone marrow to Samantha, who suffers from a rare blood disorder called thalassemia, NBC's WTHR in Indianapolis reports. The main cure for the red blood cell-destroying condition is a bone marrow transplant from a perfect match, according to Cure Thalassemia.
Enter our hero.
"I'm going to make her feel better and then I'm going to save her when she's in trouble," Jameson said in the segment above.
To raise money for costs associated with the procedure, the kids' mom, Kyrie Kessler, set up a GoFundMe page on Monday, with an anonymous donor pledging to match every dollar donation up to $500.
The family also encouraged followers on Samantha's Facebook page to purchase buttons that read, "I wear [green ribbon] for Samantha a BMT warrior."
According to bethematch.org, the donation process often involves doctors extracting the marrow from the back of the pelvic bone with hollow needles. Donors, who are anesthetized during the operation, can experience discomfort afterward.
Sounds like a job for a very brave 3-year-old. Way to save the day, Marrow Man.
Those who would like to donate can visit the GoFundMe page.
The internet's best stories, and interviews with the people who tell them. Learn more