12/05/2012 10:14 am ET

Mother Leaves Her Two Young Boys In Running SUV For 90 Minutes, Both Wind Up Dead

A Palisade, Colorado mother who admitted to leaving her two toddler sons alone in her SUV with the engine running for nearly 90 minutes last week, has now lost her second son to the tragedy.

William, 2-years-old, was pronounced dead at the scene last week, but there was some hope for 4-year-old Tyler, who was found unconscious in the running SUV and was rushed to Children's Hospital Colorado in Denver where he remained in critical condition for days. Tragically, KDVR reports that Tyler, who was suffering from brain damage, was taken off life support and died Monday night.

According to The Grand Junction Daily Sentinel which obtained investigative records, Heather Jensen, the 24-year-old mom, visited a "male friend" last Tuesday afternoon near the Powderhorn Mountain Resort. According to the police affidavit, Jensen let William and Tyler play in the snow before she put them in the car and started the engine. Once the kids were loaded into the car, Jensen says she got "into the man's truck."

About an hour and a half later when Jensen returned to her car and drove off, she immediately noticed her son Tyler was making gurgling noises, according to the affidavit the Grand Junction Daily Sentinel obtained. She pulled over and discovered her son William was not breathing so she called 911.

William was pronounced dead at the scene and Tyler was rushed to a nearby hospital. Tyler was later transfered to Children's Hospital Colorado in critical condition last week, The Denver Post reports.

Last Thursday, doctors told Robert Mathena, Tyler's step-grandfather, that Tyler had suffered severe organ damage and due to the general weakness of the young boy he could not undergo organ transplant surgery. The grandparents of Tyler were planning to get ready to fight for custody of the boy who doctors said had a "slim chance" of surviving the ordeal, KKCO reported. However, sadly there will not be a custody battle now that the 4-year-old has passed away.

The deaths of William and Tyler come about a month after the children's father, Eric Jensen, died in a car accident.

It's still unclear what caused both boys to fall so severely ill and ultimately what led to their deaths, but emergency workers were speculating that they were poisoned by carbon monoxide, according to KDVR. Authorities were investigating the SUV's exhaust system, looking for any presence of carbon monoxide as of last week. However, friends of the family have said that that the possibility of carbon monoxide poisoning had been ruled out.

Authorities said in the affidavit that there was "probable cause" to believe that child abuse resulting in death had occurred, but were still in the process of investigation and were not sure whether criminal charges would be filed against the mother.

9News reports that although the coroner has completed an autopsy of William, they are not releasing the findings because the investigation is still on-going.



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