Au wants to protest a controversial bill that has divided Hong Kong. Au’s father wants police to crack down on protesters. Mourners hold a candle during a candlelight vigil to commemorate a protester who died during a rally in Hong Kong. HONG KONG — On Friday, 21-year-old Au packed a black duffel bag with a few changes of clothes and headed out to spend the weekend with a friend back at campus. The tensions between him and his father over the biggest protests in Hong Kong’s history had boiled over the night before over. “He just blames everything on the protesters,” Au, a student at City University of Hong Kong, said of his father, who works as a border agent. “He thinks it’s totally OK to shoot the protesters.” Au’s uncle is also a police officer. Despite family pressure not to participate, Au was one of around 2 million people according to organizers — more than a quarter of the city’s population — who took to the streets of Hong Kong Sunday to demonstrate against a deeply controversial extradition bill and to call for the city’s leader to step down. The bill, originally proposed in February, would allow extraditions from Hong Kong to mainland China, which lacks human rights p...