Robert Mathena, the step-grandfather of 2-year-old William and 4-year-old Tyler Jensen, has confirmed to KKCO 11 News that Tyler has been taken off life support at Children's Hospital in Denver.
Authorities are investigating after William died and Tyler was injured after they were found in a car near the Powderhorn ski resort.
According to investigative records obtained by the Grand Junction Daily Sentinel, 24-year-old Heather Jensen told police she drove up to the Powderhorn area to meet a "male friend." The two were inside the man's truck for 90 minutes while the boys stayed in the running SUV parked nearby.
She then called 911 to report her 2-year-old boy William was unconscious, not breathing and he had no pulse shortly after she left the man and his truck.
Jensen told dispatchers around 7 p.m. Tuesday that her 4-year-old boy Tyler was barely breathing.
William was pronounced dead at the scene, while Tyler was flown to St. Mary's Hospital before being transferred to Children's Hospital in Denver.
The children's step-grandfather told KKCO he believes the two suffered carbon-monoxide poisoning after they were left in the running vehicle by their mother, Heather. The Mesa County Coroner completed an autopsy of William on Nov. 28. However the results are not available at this time due to the on-going investigation.
The boys' father died in a car accident in Rifle last month, according to KKCO.
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