What Ever Happened to Mary Day?

A 13-year-old girl vanishes in 1981. Detectives believe she was murdered. Years later, a woman appears and claims to be the missing girl. Is she an impostor? "48 Hours" correspondent Maureen Maher reports. See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.