Being a YouTuber is now the most popular aspiration for children today, according to a survey. In 2018, the site’s highest earner was a seven-year-old American toy reviewer. But the video platform has been mired in controversy over its failure to protect children. Richard Sprenger meets some of the children plying their trade on YouTube, viral sensation Rebecca Black, and visits a Los Angeles summer camp where kids as young as six learn the tricks of the trade