A few months ago I posted a story about Zach Sobiech, a Stillwater 17 year old who has osteosarcoma, a cancerous bone tumor that usually shows up in children.  After his diagnosis, he turned to music and recorded a song to serve as a good-bye letter for his friends and family.

A handful of celebrities wanted to help, so they've put together a great montage of themselves lip-synching to the song that Zach wrote and sang, "Clouds."  This is the part when you'll want to make sure you have a tissue--and can cry freely.

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