BUENOS AIRES — When Dalal Abd de Massad went to the Darwin cemetery in the Falkland Islands this week it was the first time that she had hugged the gravestone with her son’s name.

“I was finally able to cry at his grave,” Ms. Abd said of her son, Daniel. “I talked to him, told him everything that happened in these years. I hugged that white cross as if I was hugging him.”

Ms. Abd and her husband, Osvaldo Said Massad, were part of a delegation of 250, mostly family members of fallen soldiers, who traveled to the disputed islands for a ceremony to mark the identification of 90 Argentine service members who died in a 1982 war with Britain and had been buried as unknown soldiers.

For 36 years, the plaque on Daniel Massad’s grave said, “Argentine soldier known only to God.” Now, thanks to the work of forensic scientists, families have finally learned where their loved ones are buried.