MINNEAPOLIS (WCCO) — The song written by a Twin Cities teenager who died of cancer earlier this week has landed at the top of the iTunes charts posthumously.

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Zach Sobiech died at age 18 on Monday. He had been diagnosed with osteosarcoma in 2009 when he was just 13. He spent months in the hospital, underwent 10 surgeries and twice as many rounds of chemotherapy.

Last summer, when he was informed he had months to live, he responded by penning the hopeful song “Clouds,” which currently has more than 4 million YouTube hits. The tune earned him a songwriting contract, a tribute from Hollywood stars and concerts at First Avenue and the Varsity Theater.

He wrote the song as a thank you to everyone who stood by him during his battle with cancer.

“With my situation, it’s not like you can sit and be sad. It’s not fair to everybody else, and it’s not fair to yourself. Why not have some fun with the time you have left,” Zach said.

On Wednesday, the song “Clouds” reached #1 on iTunes’ chart of the most-downloaded songs, ranking above the likes of Justin Timberlake, Daft Punk, P!nk, and Macklemore featuring Ryan Lewis. (Click the picture to be taken to iTunes’ website for Sobiech’s single.)

(credit: iTunes)

(credit: iTunes)

“The kid is bigger than the Beatles right now,” said Scott Herold, the founder of Zach’s nonprofit record label, Rock the Cause.

With a home-based office and a public relations department run by interns, Herold helped Zach get “Clouds” on iTunes.

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When Zach died, the downloads picked up. There were 28,000 on Tuesday. And on Wednesday, the senior from Stillwater passed artists with million-dollar record deals.

“I kind of had this image of Zach saying to Justin Timberlake, ‘Step aside, I’m coming through,'”  Herold said.

It costs 99 cents to download “Clouds” on iTunes, and most of that 99 cents will go towards children’s cancer research.

“He wanted to be able to find a cure for osteosarcoma, but also, knowing he was going to be leaving the world, he wanted to be able to take care of the people he loved,” Herold  said. “It’s hard that Zach’s gone, but man this is really awesome. It’s beautiful.”

When all is said and done, Herold thinks “Clouds” will raise tens of thousands of dollars for osteosarcoma and children’s cancer research.

The record Zach had with friends Sammy Brown and Reed Redmond is currently #3 on iTunes.

The money from there will go to Zach’s family. It was a wish before he died that his family also be taken care of.

Zach’s funeral will be on Thursday in Stillwater.

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CaringBridge said the Sobiech family wanted any memorial offerings to be directed to the Zach Sobiech Osteosarcoma Fund in lieu of flowers.