At age 14, Zach was diagnosed with osteosarcoma. Later, he was given a year to live. He decided to form a band and write a song about the experience. He put together a video which went viral and then other musicians began releasing tribute versions of the video. One of them features Rainn Wilson, Sara Bareilles, Jason Mraz, Bryon Cranston and Colbie Caillat. Both are below and are quite moving.