Transcript for New details on the death of a family from Iowa vacationing in Mexico

emerging about a family vacation horror. The parents and two young children found dead in their condo in Mexico. The autopsy pointing to some kind of toxic gas as responsible. Here's Marci Gonzalez. Reporter: Tonight, investigators trying to identify what gas killed a family of four on vacation in Mexico. Looking in an oven, checking exhaust pipes, checking this condo where Kevin sharp, his wife, Amy, and their children found dead Friday. Mexican officials ruling the cause of death, asphyxiation by inhalation of toxic gases. The last few days have been an absolute nightmare. This is something you watch on TV, not something that happened to our family. Reporter: The sharp family renting the condo on spring break through the website vrbo. Vrbo saying they've removed the property from their site. Friends holding a candlelight vigil back home. Where Kevin was a salesman and stock car driver and Amy worked from home. Family describing Adriana as a fashion diva. Saying sterling was quiet and loved being outdoors with his dad. They're going to be missed a lot. Reporter: Experts say this is a reminder of the importance, when traveling, of bringing a device like this that can detect the odorless fumes. Tom? Marci, thank you. And eagles defender Michael

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