( CNN ) -- Zach Sobiech , 18 , passed away Monday morning , surrounded by family and friends . In the past few weeks , donations to Zach 's cause -- the Children 's Cancer Research Fund -- skyrocketed , as did downloads of his song , `` Clouds , '' which at the time of his death had more than 2.9 million page views on YouTube . Listen to `` Clouds '' `` We 'd like to thank those people who listened with their hearts and helped Zach bring his message and his music to the world , '' the Sobiech family said in a statement . When he was 14 , Zach was diagnosed with osteosarcoma , a type of bone cancer that mostly strikes children . His prognosis was n't great . Last May , with no more treatment options , he was given a year to live . Zach began writing music after his cancer was diagnosed . His mom , Laura , was cleaning the family room downstairs last year when she found a folded-up piece of paper . She unfolded it to make sure it was n't a homework assignment . `` I read through it and then I realized what I was reading , '' she said . It was his first song , `` Clouds . '' Zach wrote it for himself and his family . He wrote many more in the following years . Watch celebrities sing along to `` Clouds '' `` I fell down , down , down into this dark and lonely hole , '' he sings at the beginning of the song , his voice beautiful , mellow -- kind of reminiscent of Jack Johnson 's . When Zach 's song was posted to YouTube last year it quickly went viral . Recently dozens of celebrities posted a response -- joining forces to lip sync to Zach 's voice singing `` Clouds . '' `` And we 'll go up , up , up , but I 'll climb a little higher , '' sang Jason Mraz , Anna Faris and Rainn Wilson . `` Go up in the clouds because the view 's a little nicer up here , my dear , '' sang Bryan Cranston and Rachel Bilson , Ashley Tisdale and Colbie Caillat . `` It wo n't be long now , '' sang the Lumineers . `` If only , '' sang Sarah Silverman , `` I had a little bit more time . '' It was a hello to Zach , and a farewell . It was a collective expression of love and gratitude . The motley crew of celebrities on the video was assembled by Wilson , an actor , and director/actor Justin Baldoni , who directed a short documentary about Zach for his compelling online reality series , `` My Last Days , '' which runs on Wilson 's SoulPancake YouTube channel . Get to know Zach . `` Going out to see Zach in Minnesota was one of the greatest experiences of my life , '' said Baldoni . `` To make the choice to be happy despite whatever sad or tragic circumstances you may be living through ... he is this old soul who inspires everyone he meets . You leave and you think : ' I want to be a better person . ' '' Watch Baldoni 's film and you can see why . There 's Zach , a fresh-faced Minnesotan teenager , in one of the opening frames , saying : `` I want everyone to know : You do n't have to find out you 're dying to start living . '' He tells us at the beginning of the film : `` You know most people live kind of in the middle , in between 'all your dreams come true ' and 'you 're dying , ' and it 's a very comfortable place to live . I 'm living on the two extreme ends , so you have really , really good days and you have really , really bad days . '' He lived on those extreme ends for the better part of the past four years . And how gloriously . In his final days , Zach slept a lot . Once in awhile he was able to muster up enough energy to bring out his guitar and play . `` It 's those times when we remember how it used to be , '' said his mom . She told me about a trip the family took last year , `` a sort of pilgrimage to Europe , '' with 10 intense days of sightseeing . `` We packed a lot into those 10 days , '' she recalled , `` and maybe these past 3Â½ years have been like that pilgrimage . I have n't had the chance to let it sink in . I do n't let myself go to that place of grief . There will be plenty of time to think about what we have lost later . '' And maybe , she said , that is the lesson here : that no matter where you are in life , look at what you have and be grateful . It 's the kind of thing you hear all the time , but putting it into action takes some work . `` That 's what Zach 's always been really good at : recognizing what is good and being grateful for it , '' Laura said . `` He taught all of us how it 's done . '' Taylor Engel , one of the YouTube commenters on Zach 's video , writes : `` Well , you got a 6 ' , 220 pound man sobbing his face off here . Prayers and thoughts with you , Zach ... I hope someday I can be half the man you 've become . '' So many of us felt the same way as we watched his video for `` Clouds '' -- grateful for having had him walk among us , albeit for a short time , as he sang : `` And maybe someday I 'll see you again . We 'll float up in the clouds and we 'll never see the end ... ''
Zach Sobiech was diagnosed at 19 with osteosarcoma , a bone cancer . Last May , Zach was given a year to live after doctors ran out of treatment options . Zach 's song ` ` Alive '' went viral on YouTube ; now they have posted a video .