LOS ANGELES (Reuters) - Boy band the Backstreet Boys - now all grown men - on Monday marked their 20th anniversary and their upcoming world tour by getting a star on the Hollywood Walk of Fame. "Backstreet is Back ... and we aren't going anywhere," Nick Carter, 33, told fans as all five members of the 1990s band gathered to unveil their star - located right next to another popular boy band, Boyz II Men. The close harmony singers were visibly emotional as they thanked their families and fans for their support over the years. "What an honor it is," said Kevin Richardson, 40, holding back tears. ...