Buried at the edge of a Chicago Catholic cemetery are an elderly person’s remains marked only by a cement cylinder deep in the ground labeled with the numbers 04985. The person died in 2015 at a nursing home not remembering much, including their own name.

They went by Seven.

Now police specializing in missing people and cold cases have discovered Seven’s identity in one of the most unusual investigations the Cook County sheriff’s office has pursued and one that could change state law. Using post-mortem fingerprints, investigators identified Seven as 75-year-old Reba C. Bailey, an Illinois veteran missing since the 1970s.

The breakthrough is bringing closure to generations of relatives and friends. But whether they knew the name or the numeral, the investigation has unearthed more mysteries about how Reba, a Women’s Army Corps veteran raised in a large family, became homeless with no recollection, aside from wanting to be identified as a man called Seven.