The children along with their families and hospital staff at the Kimmel Cancer Center put together a video of the kids lip-synching to the One Direction song, "You're Beautiful."
They posted it on You Tube and it was barely up for two days before one of the band's young heart-throbs saw it, loved it -- and sang it from the rooftops today.
"Just seen this amazing video from @HopkinsKids," the band's Liam Payne Tweeted. "Love you guys! big hugs from meeeee and the boysssss."
Check out the video here:
With the endorsement of Payne, who has nearly 6 million Twitter followers, the video could easily go viral.
Payne's Tweet has already been shared this afternoon more than 8,000 times -- in less than an hour.
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