Four family members in a rural community were brutally killed in the middle of the night. A teen-age waitress was found beaten to death. A young immigrant girl disappeared without a trace. 48 Hours examined three long-unsolved murder cases that stymied police and haunted families. 48 Hours initially started reporting on one of these cases in 1996. Find out how hard work and new technology can play a role. Here's an update. In December 1978, four members of the Huling family were shot and killed in their rural home. One young boy, Bill Huling, survived. No one was arrested. Correspondent Erin Moriarty reports on the investigators trying to crack the case years later. With the help of a 48 Hours broadcast, new witnesses emerged. Investigators focused on a convicted murderer and rapist named Joe Ture, and took a second look at a mysterious toy car. Police explored a connection between the Huling case and the murder of a young waitress. Reyna Marroquin left El Salvador in 1966, eager for a new start to New York. Then she disappeared. Her family never knew what happened. Susan Spencer tells the story. When Marroquin's body was found last year hidden in an industrial drum, detectives went to work. Could they unravel a 30-year-old mystery?