Celebrities Honor Young Cancer Patient by Covering Viral Hit “Clouds”

"When faced with months to live, how do you say goodbye?" That's the question posed by 17-year-old cancer victim Zach Sobiech, who wrote a viral hit song, "Clouds," as his answer. The tune touched the hearts of many, including a slew of celebrities who have filmed their own take on "Clouds" to raise awareness and research funds in Sobiech's honor.

The idea was spearheaded by "The Office" star Rainn Wilson, who gathered up friends from the worlds of music and acting to pay tribute to Sobiech, who is fighting osteosarcoma--a rare form of bone cancer that is particularly aggressive and deadly.

It's no surprise that Sobiech's song has affected everyone from civilians to celebs: It's hard to keep a dry eye when listening to the lyrics, which include such quiet but moving sentiments as "Be ready to live and it'll be ripped right out of my hands," "If only I had a little bit more time with you," and the chorus "We'll go up, up, up/But I'll fly a little higher/We'll go up in the clouds because the view is a little nicer."

Enjoy spotting all the famous faces in the video--but if you'd like a cheat sheet, the list of participants singing along to Sobiech's affecting tune includes Brian Cranston, Sarah Silverman, Ashley Tisdale, Colbie Caillat, Chris Pratt, Anna Faris, Jason Mraz, Sara Bareilles, Andy Grammer, Jenna Fischer, Angela Kinsey, Jenna Elfman, Jack McBrayer, Lumineers, Jason Derulo, The Mowgli's, Rachel Bilson, Kina Grannis, Passenger, Creed Bratton, Tyler Hilton, Mark Duplass, Josh Gad, Jason Wade, Paul McDonald, Ed Helms, Phillip Phillips, Justin Young, and Alyssa Shouse.

Love Sobiech's ballad? You can download it here. All proceeds support the Zach Sobiech Osteosarcoma Fund. You can also make a donation directly at the Fund's webpage.

Sobiech was diagnosed with the disease in 2009, when he was just 14 years old. He's since endured a number of treatments, including a hip replacement. Last May, doctors discovered that the cancer had spread, and pronounced there is nothing more than can be done.