After several American tourists were found dead in their rooms at a resort in the Dominican Republic, the family of a Pennsylvania woman said she died last year while vacationing at the same resort.

According to Fox29 Philadelphia, Yvette Monique Sport, 51, was staying in the Bahia Principe Resort in Punta Cana last June when she died. Her relatives told the local news outlet Sport had a drink from the minibar inside her room before going to bed and dying in her sleep.

Her death certificate listed “heart attack” as the cause, although her family has their doubts.

"She was 51 years of age, relatively healthy, no reason for her to go on vacation and die so suddenly," her sister, Felecia Nieves, told FOX 29.

Sport was vacationing there with her fiancé, Howard Taltoan, and their friends.

The circumstances surrounding Sport’s death mirror those of the American tourists who died within five days of each other last month at resorts owned by the Bahia Principe Hotels & Resorts group.

On May 25, Miranda Schaup-Werner of Pennsylvania collapsed and died after having a drink from the minibar in her room at the Luxury Bahia Principe Bouganville. Then on May 30, Edward Holmes and Cynthia Day, an engaged couple from Maryland, were found dead in their room at the neighboring Bahia Principe La Romana. Police have not said whether Holmes and Day drank from the minibar.

In all three cases, the cause of death was listed as respiratory failure and pulmonary edema, which means having fluid in the lungs.

"It makes me question at this point is this cause of death even true," Nieves told FOX29 after the new deaths were reported.

Although Sport's family was told they would receive a toxicology report, they still have not.

"We were promised within three months that we would receive a toxicology report to this day, which is almost a year now we’ve got nothing," Nieves said.

Now, Sport’s fiance thinks the United States needs to intervene.

"I think the State Department needs to step in and investigate these deaths. Something is not right," Taltoan told FOX29.

According to a report by the U.S. State Department, 13 American deaths were reported in the Dominican Republic in 2018. However, the report did not list Sport’s death, because it was declared by Dominican authorities to have been caused by natural causes.

"That’s even more disturbing because why wouldn’t she be listed?" Nieves told FOX29. "My sister Yvette is probably one of many people unreported and unknown because families like mine even shocked decided to sit on it didn’t know if true or not true just didn’t make sense.”

Sport’s family says they will continue fighting for answers.

"Hopefully, some of the things that happened in the dark do come to light," Nieves said.

The Bahia Principe has not yet revealed if any other Americans have died on its properties in the last two years. In March, Portia Ravenelle and Orlando Moore died on their way to the airport after staying at the Grand Bahia Principe Cayaco in Samana.

Dominican Republic police believe alcohol, speeding and dark roads may have caused Moore to lose control of his rental car and crash into the Caribbean Sea

It remains unknown if Moore and Ravenelle had anything to drink from the minibar in their hotel room before leaving for the airport.