Transcript for Green brothers talk about new book, secrets to success
We are back with the green brothers, they're best-selling authors and John wrote "A fault in the stars and hank has a new book called "A beautifully foolish endeavor." Will reeve spoke to them about their success. Good morning. Good morning. Reporter: Even though together they've amassed billions of views on YouTube and written number one best-selling books and made hundreds of educational videos and podcasts brothers John and hank green are creator second, brothers first. John, writer of "The fault in our stars" which became a hit movie -- What's your story? I was diagnosed when I was Not your cancer story. Reporter: He's also the number one hype man for his little brother hank's new book, "A beautifully foolish endeavor." It's a story of young people trying to make their way in this weird, wild new world of ours. Obviously hank didn't see a global pandemic coming when he was writing this book, but he did see something coming. I was astonished by the parallels between the world of the novel and the world I find myself living in right now when it comes to how we cope with isolation. When it comes to how we use technological tools to humanize one another. But also at times to dehumanize one another. Good morning, hank. It's Friday. Reporter: Their forray into YouTube began over a decade ago as a sibling social experiment. Good morning, John. Good morning, hank. Reporter: For a year their videos was the only way they talked to each other. They started in 2007 because we weren't close and the hope was that through that project, we would become closer and, boy, did it work. I mean, now hank and I talk every day whether we want to or not. Do you ever get competitive with one another? There is a certain amount of one-upsmanship where I want to make something different or has a better joke than the last video John made. I don't feel envious of any part of hank's life. Our videos have been viewed a lot over 13 years. Our educational channels are much more successful. Crash course of scishow have had over 2 billion views. Justin Bieber and what do you want your brother to know? I want him to know that he's brilliant and wonderfully talented but most of all what makes me proudest of hank is his kindness and his generosity, often quiet, private generosity. And what would you say? I want him to know he's really effective and brave and a good dad and a good person. Reporter: For "Good morning America," I'm will reeve, ABC news. Really good brothers. "A beautifully foolish endeavor" is out now.
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