Transcript for Police Search for Answers in Mysterious Death of 2 Sisters
That vacation mystery. Two American sisters enjoying a trip at a luxury resort on a tropical island before they were found dead in their room. Investigators and family searching for answers. Mara schiavocampo is here with that. Good morning. Reporter: Good morning, robin. A mystery indeed. The mother and brother of those sisters have now travelled to the Seychelles to find out what happened and to bring them home. This morning, two sisters' dream vie occasion turned into one family's nightmare. 42-year-old robin korkki from Chicago, and her sister, 37-year-old Annie korkki from Denver, found dead in their room. Mysteriously passing away on a trip of a lifetime. You're talking about pulmonary edema. That's a big deal. I would look for drug use, either directly or indirectly by someone else. Reporter: The pair both worked in banking. Robin's linkedin account showing she was a trader. They shared their love of travel on social media. They were staying in a luxury $2,000 a night resort in the Seychelles. The island known for beautiful beaches and high-end resorts. The trip was part of a nearly month-long vacation many Africa. Days after posting these pictures, a terrible end. The hotel saying the pair was discovered when an employee of the hotel tried to wake them in their villa. The day before, the pair had been seen drinking at the resort until about 6:45 P.M. Later helped to their rooms by staff at 8:15. When discovered the next morning, no visible signs of injuries were found on the bodies. An autopsy determining the cause of death for both sisters as acute pulmonary edema. Annie also suffering a sir recerebral edema. This is something they ingested or inhaled that caused their death, based on their age and health. Reporter: A pulmonary edema could be the reason why. There will be a toxicology analysis. Tonight's "20/20" takes a
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