Cause of Death Revealed for Sisters Found at African Resort But their family is still searching for answers By Michael Harthorne, Newser Staff Posted Sep 30, 2016 12:16 PM CDT 49 comments Comments American sisters Robin and Annie Korkki were found dead last week at a luxury resort in the African nation of Seychelles. (Facebook)American sisters Robin and Annie Korkki were found dead last week at a luxury resort in the African nation of Seychelles. (Facebook) (Newser) – Two American sisters found dead at a $2,000-a-night luxury African resort last week died of acute pulmonary edema, otherwise known as fluid on the lungs, NBC News reports. According to the Minneapolis Star Tribune, staff found 37-year-ole Annie Korkki and 42-year-old Robin Korkki dead in their villa at the Maia resort in Seychelles on Sept. 22. They had no visible injuries. While both sisters had excess fluid in their lungs, Annie also had fluid in her brain. Officials haven't given any suggestion as to the cause of the fluid, the Chicago Tribune reports. Autopsies were performed Wednesday. There are many possible causes for fluid in the lungs, including a virus, a drug overdose, poison, and heart failure. Both sisters were described by friends as "physically fit and active." One expert tells the Star Tribune it's "odd" for two people to suffer fatal acute pulmonary edema at the same time, which makes it seem like there was an "environmental cause" or "potential infection." Family hopes a pending toxicology report and ongoing police investigation will shed light on what happened to the sisters. "There are more questions than answers," brother Chris Korkki tells NBC.