The pop star talks about the legacy of the Greenwich Village bar that sparked the LGTBQ rights movement and her years of advocating for the community. WATCH NIGHTLINE EPISODES: abc.go.com/shows/nightline ALSO AVAILABLE ON HULU: hulu.tv/2wSmSrZ #nightline #christinaaguilera #stonewall #lgbtq #gay #singer #celebrity #abcnews