Parents of black children have, at some point, had the talk. This conversation teaches children how to remain calm and how to react in the event they are stopped by police. PBS is examining this generations-long tradition. The Talk: Race in America is a two-hour documentary about the conversation taking place in homes and communities across the country. It will air at 8 p.m. tonight on PBS (KERA) and again at 2 a.m. on Thursday.