After 65 years,
www.forensicmag.com
(^article on the genetic trail that the researchers followed)
With this quote:
//Eventually, Fitzpatrick and Gillis gave the Philadelphia Police Department
leads for the maternal side of the child’s family. Detectives made contact with the family, obtaining a DNA sample from a living relative. After further testing, Fitzpatrick and Gillis were able to confirm the identity of the child’s birth mother.
This cracked open the case and made people invest the time to piece together SNP markers, leading to more information.
(And no one is "pure Albanian" because either people came there after the first Europeans arrived circa 40,000 years ago OR they share what is called "Older European" or "Paleo-European" markers which are not specific to any group and which nearly every single European has (except for people arriving later).
Albania has been inhabited since the Paleolithic, is what I'm saying. And with some stable elements in their genome which they
share with non-Albanians.