John and Hank Green’s vlog is a multimillion-dollar philanthropy machine

Released in January 2012, John Green’s young-adult novel, The Fault in Our Stars, is one of the best-selling books of all time. It was made into a Hollywood blockbuster in 2014, and has gone on to sell more than 23 million copies. What is less well-remembered is that the novel was top of the Amazon book charts and on The New York Times bestseller list months before it was even published, with pre-orders of 150,000 copies. This was down to John’s hyper-engaged online fanbase,…