4-year-old Dominick Wilk's body temperature was 107 degrees after he was freed from the trunk, ABC-57 News reported.
Two young brothers found by their mother in the trunk of her car Friday have died.
It happened in New Carlisle, Ind., in the driveway of the family's home, on a day when temperatures reached into the mid-80s.
Jaqueline Wilk found her two boys, Isaac Dunner, 2, and Dominick Wilk, 4, locked inside the trunk around 3 p.m., local police said. No one's sure how long the boys were trapped before they were found. How she came to discover the boys "is all part of the investigation," police told WSBT-TV.
Neighbors said they saw Wilk crying and screaming as police performed CPR on the children. The father of one of the boys rushed to the home, and "almost fainted," according to a neighbor, who told the TV station police had to hold the man up while they talked to him.
Isaac died shortly after he and his brother were found. Dominick held on until Saturday.
Police say Wilk is cooperating with the investigation, but at this point, it seems to be just a tragic accident.