Lily Glidden's body was found Jan. 18, five days after she went missing while on a walk in Thailand's Kaeng Krachen National Park.
The injuries to her body appeared to be consistent with elephant trampling.
"We believe that what happened to Lily was a result of unknowable and unusual circumstances which she must have been unable to foresee or prevent," her family said in a statement.
"Lily was very aware of the dangers of working with wildlife, and not a person to court foolish risks, particularly where animals were involved," the family statement said.
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