Transcript for The tourists killed by toxic gas in Mexico

couple found dead in Mexico, victims of that silent killer, carbon monoxide. And tonight, their family is now struggling to bring their Bolds home. Here's ABC's Victor Oquendo. Reporter: Tonight, the family of Ed winders and Barbara Moller struggling for answers and with Mexican officials to return the couple's bodies after the two were found dead. Both killed inside their air bnb by carbon monoxide poisoning while vacationing in San Miguel de Allende. It's hard to make sense of something that doesn't make -- you know, we all pass at some point in time, but it just seems wrong. Reporter: The landlord, after not hearing anything from the couple, finding them nearly two weeks ago. Mexican officials now working to see if a faulty heater was the source of the carbon monoxide. Carbon monoxide is colorless, odorless and poisonous. Symptoms can range from headaches, to loss of consciousness, and ultimately get death. Airbnb saying, we are deeply saddened by the loss. The family eager to bring the two home. My dad was my best friend, my sister's best friend. He's just a larger than life figure. Reporter: The family now urging anyone traveling this holiday season to a vacation home to ask about carbon monoxide detectors, and if they don't have one, you can bring one just like this. Victor, thank you.

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