An Alaskan family is mourning the death of a 10-year-old boy after he fell victim to a carbon monoxide leak that originated in the refrigerator in their cabin.

When carbon monoxide, often referred to as a "silent killer," leaked into their cabin on Aug. 20, Sarah and Matt Klebs thought that they, their 8-year-old daughter and their 10-year-old son were suffering from the flu. Now the grieving parents are speaking out about a danger they did not even consider at the time.

"How would you know? Prior to this, I never would have thought about it," the heartbroken mother told the Alaska Dispatch News in a recent interview.

Sarah Klebs was at the cabin with two of her children, Caroline and Gavin, when the leak happened. Connor Klebs, 14, was staying with friends that weekend and Matt Klebs was working.

Sarah said that headaches soon escalated into vomiting that night and, before she knew it, she was sending messages to concerned family members about what was happening. She said she eventually wasn't able to respond to replies and couldn't remember why.

CBC News story from 2014 on the dangers of carbon monoxide poisoning explained that it is "easy to confuse the symptoms of carbon monoxide exposure with the flu or other medical problems," because the symptoms, like headache, fatigue, trouble thinking, dizziness and nausea are similar.

By 9 p.m. on Sunday, Aug. 20, the family that Connor had been staying with realized something was wrong when Sarah didn't pick up her son as planned. When they arrived at the cabin to check on the family, they found the three unresponsive. While Caroline and her mother were saved with the help of intensive emergency treatment, Gavin did not make it.

GoFundMe campaign was started for the family by Seth McMillan to help the Klebs family cover medical costs. So far the effort has raised more than $26,000.