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Jason Kelce and Travis Kelce have reached the mountaintop in more than just football. Now, the brotherly NFL duo is conquering the music industry as well.

The Kelce brothers' Christmas song "Fairytale of Philadelphia" has made it all the way to No. 1 on Billboard's Rock Digital Song Sales charts.

The weekly chart ranks the bestselling rock songs in the United States. "Fairytale of Philadelphia" is also sitting atop the Holiday Digital Song Sales chart. Billboard previously didn't have a Holiday Songs chart, but recently decided to reinstitute the chart. 

The holiday song sold 4,500 copies during its second week of release after debuting at No. 2 last week. 

During an episode of Jason and Travis' "New Heights" podcast last week, the Philadelphia Eagles center celebrated the song reaching No. 1 on iTunes and gave thanks to Taylor Swift fans around the world.

"The Swifties came out," Jason Kelce said.

"Fairytale of Philadelphia" is included on the upcoming Christmas album "A Philly Special: Christmas Special," which also features Eagles teammates Jordan Mailata and Lane Johnson. The album will be released on Dec. 1, and all proceeds will beenfit local Philadelphia charities.