Transcript for American family of four dies of toxic gas in Mexico

We're back with the spring break mystery and the new concerns about vacation rentals, after an American family of four died in Mexico. Police say they were killed by toxic gas inside their rented condo. So frightening and tragic. Investigators in Mexico are still trying to figure out what caused the tragedy. A cousin of the family said, they went to sleep and never woke up. This morning, new concerns over the safety of vacation rentals abroad after one family's spring break get away turned deadly. 41-year-old Kevin sharp and his wife, Amy, surprising their two children, 12-year-old sterling and 7-year-old Adrianna with a trip to this condo earler in in month. When the Iowa family didn't make the return flight home, their loved ones knew something was wrong. My mother lost her youngest daughter. And she's like all of us got the support of everybody rallying around us. Reporter: Mexican authorities finding the family of four dead inside the condo Friday. They say due to asphyxiation by inhalation of toxic gases. The attorney general saying there were though science of violence nor evidence O suggest disturbances inside the room. When they found them, both kids looked like they were watching TV. The parents were in the bed watching TV. So there was to foul play. Reporter: These photos showing firefighters and a forensics team scouring the condo Saturday. Inspecting the gas installation for any leaks. Mexican authorities saying it will take about ten days to determine the type of toxic fume that caused their deaths. Despite travel warnings due to the level of crime, Mexico remains one of the top five spring break destinations for Americans. The sharp family found the condo through vacation home rental company vrbo. Who said they have since removed the property from its sight. The safety standards for home rentals are far different than hotels. If you're renting, the minute you zboo into that room, that apartment, check the smoke alarm and the carbon monoxide detector. Make sure they're working. Reporter: That is something to think about now. While the authorities have yet to determine the type of gas in the condo, some travel experts suggest to bring your own carbon monoxide dedekter. Bring it with you. On the plane or in the baggage. Whatever. It determines you have to know the battery source. Sometimes you can bring them on your checked luggage. Sometimes ve to pack them. Because the batteries can have an issue with the planes. Check beforehand whoot type of deferkt you're bringing. Certainly worth it. Gosh. We all just think -- it doesn't cross our mind when we're renting someone else's -- Your home away from home, you imagine. Thank you, so much, Amy. Appreciate that.

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