Tanya Ruiz was last seen at the Edwards Ranch near Piru, CA, where she lived with her husband. Tanya had been visiting her grandmother the preceding three or four days. When she did not meet her grandmother on Sunday as planned, the family began to search for Tanya.
After trying for a month to locate Tanya, her mother reported her disappearance to the sheriff, whose deputy eventually interviewed her husband. According to the deputy, her husband seemed unconcerned about his wife's whereabouts, and told the deputy that Tanya had taken with her $150 to $200 and some clothes when she left.
Without any leads, the case was closed until the discovery in 1979 of the bodies of her husband's subsequent wife and her son, whom he buried in his backyard. (Information retrieved from NamUs.gov)