An unusual relationship between a 12-year-old musician and a cancer-stricken 4-year-old is helping to raise awareness of a rare form of childhood cancer.

Anyone who's lived in or visited a big city knows that street performers, or buskers, can be found on every corner -- you stop and listen, and toss a few coins in their guitar case. But Abby Miller stands out, and not only because she's just 12 years old.

Abby takes her music to the streets to raise money and support for her 4-year-old friend, Taylor Love, who suffers from a little-understood cancer, neuroblastoma, which attacks the central nervous system. According to a story on CNN, Taylor is in remission now, but the disease has a very high risk of recurrence and there is little research on the illness.

Abby was spotted this week in front of Washington, D.C.'s, Union Station, but she's traveled far and wide to show her support for Taylor. The two were brought together by a mutual family friend, Mike Gillette, according to CNN, and he's taken the tween chanteuse to New Jersey and Virginia to help her raise critical awareness about the devastating disease.

Abby doesn't just collect money; she also asks her fans to fill out "Love Notes," or small cards with encouraging words. Each night Taylor's mom, Aimee Love, reads them to her daughter.

"Her mom reads them to her before she goes to bed at night," Abby told CNN. "Taylor gets excited for them and she loves getting them read to her because she likes knowing that people are supporting her and people are actually thinking of her."

Gillette estimates that Abby has collected several hundred of the love notes -- and raised thousands of dollars.

Abby, who told CNN that her preschool buddy is "the most happy girl in the world," is proud of Taylor's strength of character. The little girl has had to endure multiple, painful treatments for her cancer, but she still has a strong spirit.

"She's so much fun to be around," Abby said. "She's a little 4-year-old girl but she's got a heart of like a thousand grown adults."

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