Watch 7-year-old cancer patient sing 'Fight Song' with Rachel Platten

/ Source: TODAY

A 7-year-old cancer patient got the surprise of a lifetime when pop star Rachel Platten joined him at his bedside for a duet of her hit, "Fight Song."

Jeremiah Succar was diagnosed with atypical rhabdoid teratoid, a tumor that grows in the brain and spinal cord, in June, and he's being treated at Children's Hospital Los Angeles. During treatment — he recently started his third round of chemotherapy — "Fight Song" has become the young boy's anthem for staying strong, his mother Jessica Frontela told

"They do music therapy in the hospital, and his music therapist introduced the song to him," Frontela said. "Since that day he would YouTube it, and watch it and learn the lyrics. He would sing it with every IV change, every procedure. It was just his little way of escaping the pain."

After realizing what an impact the song had on their son, Jeremiah's parents started the #RachelMeetJeremiah hashtag on social media, which caught the singer's attention.

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"She contacted us herself, and she was replying to tons of people on social media saying she was going to try her best to come out, and she made it happen," Frontela said. "She was really humble and sweet."

As for Jeremiah, he called the meeting "pretty much amazing."

"It was the best day of my life," he told

While the heartwarming visit happened on August 21, the hospital posted a video of the duet online Tuesday in honor of the start of Childhood Cancer Awareness Month. At the end of the clip, Jeremiah sweetly asks for Platten's autograph.

Frontela said she tried her best to keep Platten's visit a secret from her son, but "he kind of had an idea" the singer was coming from watching the buzz on social media.

Platten, 34, posted about the "amazing" visit on her Instagram page, writing, "I love you Jeremiah, thanks for inspiring me and rocking out with me!!!"

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