(CNN) -- Five days before a Maryland couple was found dead in their hotel room in the Dominican Republic, a Pennsylvania woman collapsed and died at the same resort shortly after she checked in, a family spokesman says.
Miranda Schaup-Werner, 41, of Allentown, Pennsylvania, had just checked in on May 25 and enjoyed a drink from the minibar at the Bahia Principe Hotel in La Romana, family spokesman Jay McDonald told CNN affiliate WFMZ.
She was with her husband, Dan Werner, at the resort celebrating their ninth wedding anniversary when she suddenly collapsed in her hotel room, he said.
"At one point, she was sitting there happily smiling and taking pictures and the next moment she was in acute pain and called out for Dan and she collapsed," McDonald said.
"He was understandably in shock but the whole thing was just so stunning."
Schaup-Werner died of respiratory failure and pulmonary edema, according to authorities.
Couple dies a week later
Five days later, on May 30, Maryland couple Edward Nathaniel Holmes, 63, and Cynthia Ann Day, 49, missed their scheduled check out time at the same resort. Hotel employees checked on them and found them dead, police said.
When Schaup-Werner's family heard about the couple's deaths, they notified the State Department of the similarities and requested an investigation, according to McDonald. He said Schaup-Werner was healthy before her death.
"What we thought was a freak event now we don't know," he said.
CNN has reached out to the resort and the Dominican Republic National Police for more information.
Three Americans in five days
The two families are searching for answers after the loss of their loved ones in the same resort five days apart.
In a statement to CNN, the State Department confirmed the deaths of the three US citizens in the Dominican Republic last month.
"We offer our sincerest condolences to the families for their loss," it said.
After Day and Holmes died, the Dominican Republic National Police said an autopsy concluded the couple had respiratory failure and pulmonary edema, a condition caused by excess fluid in the lungs.
Various medications meant to treat high blood pressure were found in the room, police said. There were no signs of violence in the room.
All three checked in on same day
Holmes and Day were engaged, and were from Prince George's County, Maryland, relatives told CNN affiliate WBAL. They were supposed to fly back home the day they were found.
Days before their deaths, Holmes posted Facebook photos of the couple enjoying their time in open waters.
"Boat ride of a lifetime!!!" one caption said.
The three Americans all checked into the hotel on May 25 -- the same day Schaup-Werner died, the affiliate reported. The couple was checking out five days later when they were found. Their bodies were transported to the Dominican National Institute of Forensic Sciences for an exam.
"We are deeply saddened by the incident at one of our hotels in La Romana, Dominican Republic, and want to express our deepest condolences to their family and friends," Bahia Principe Hotels said in a statement after the couple's death.
La Romana is on the Dominican Republic's Caribbean coast, and has a population of about 130,000.