In August, a married couple, their one-year-old daughter, and their dog died under mysterious circumstances while hiking in the Sierra National Forest near Yosemite National Park. After ruling out suicide or murder, authorities explored whether toxic algae or even poisonous gas from nearby mines could have killed them.
Just yesterday though, Mariposa County Sheriff Jeremy Briese announced the cause of their death: hyperthermia, defined by the NIH as "an abnormally high body temperature caused by a failure of the heat-regulating mechanisms of the body to deal with the heat coming from the environment."
Briese noted that an empty 85-ounce water bladder was found with the couple, and no other water containers were present.
"The question of why can never be answered and will remain with us," Chung and Gerrish's family said in a statement. "Our hearts will never forget the beautiful lives of Jonathan, Ellen, Miju, and of course Oski. They will remain with us wherever we go, and whatever we do."