FORT WORTH, Texas (CBSDFW.COM) – There is still no closure for the family of a Fort Worth couple who died in late May while on vacation in Fiji.

David and Michelle Paul were parents to a 2-year-old boy. 

Michelle’s father, Marc Calanog, spoke to CBS 11 News about her death from his home in Henderson, Nevada.

“I don’t know when this investigation will be done.”

David and Michelle Paul (credit: Marc Calanog)

The circumstances surrounding the couple’s death have caught the attention of health officials in Fiji, investigators from U.S. Centers for Disease Control and authorities with the World Health Organization, according to CBS news.

Calanog said the two fell ill to an unknown cause and sought treatment at a Fiji hospital, but their mysterious conditions worsened.

Michelle died on May 25 and her husband David passed two days later.

Calanog said the flu was ruled out, but not many other details have been given.

He added, “You know my daughter’s death. I would really like to have the conclusion, but I want to have the knowledge of what happened and that is not happening.”

Those who knew the couple say they were vibrant and in good health, which makes this mystery that much more bizarre and perplexing.

While he waits on answers Mr. Calanog said his focus is now caring for the couple’s child.

He said, “Getting depressed will not bring my daughter life again, but we have here a 2-year-old grandson that needs all the care he needs and we need to have all the strength to do this.”