These two cases are very tangentially rated to Cooper.
First, a young woman who went missing in 1969 has been identified using investigative genetic genealogy. This is the same technique that would need to be used to give Cooper a name. Moreover, her remains were found on Sauvie Island just a few miles north of Tena Bar:
https://people.com/human-remains-identified-as-portland-teen-who-went-missing-in-1970-8599722
Second, the story of a young girl who went missing from Vancouver, WA just two weeks after the DB Cooper hijacking. Her clothing and other belongings were later found near Battle Ground, WA. She is believed to be a victim of serial killer Warren Forrest. Coincidentally, a body was found at the Cedar Creek Grist Mill which is just south of Lake Merwin in spring of 1972. At, the time it was thought that the remains could be that of DB Cooper. That body was later identified at Barbara Ann Derry, who was also a victim of Warren Forrest.
https://www.nbcnews.com/feature/cold-case-spotlight/sister-still-hoping-answers-jamie-grissim-s-disappearance-n691386#
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