When Valerie Starks, a mother from Denver, found out that her 13-year-old daughter was posing as an older teenager to post raunchy photographs to the Web, she took to social media to teach her a lesson. She berated her child in a Facebook video that spread like wildfire in May 2015—in less than a week it had more than 11 million views. Starks was not alone. In the past year numerous parents have used social media to punish their kids.