EL PASO — El Paso County Sheriff's deputies say a murder victim's son helped them solve a 36 year-old cold case. Major Chester Garrett was killed back in 1977. According to an affidavit released Monday, Chester's son Patrick came forward in January to tell investigators that he knew how his father died. Patrick Garrett says several decades ago, Chester's step-son Roger admitted to Patrick that he killed Chester. Roger Garrett allegedly hit Chester in the head with a baseball bat, while Chester's wife, Lisbeth stabbed him several times in the kitchen of the family's home. The pair allegedly dragged the body into Chester's car and left him in the desert. Patrick was only 12 at the time. He says he remembers a red stain on the floor of the garage, and having to use acid to clean it up. 74 year-old Lisbeth Garrett was a long time speech teacher at Eastwood High School in El Paso. She and Roger were arrested last week and are now charged with murder.