A southern Illinois man has pleaded guilty in the death of his 23-month old son, who died in a hot car while his father passed out after drinking.  The Belleville News-Democrat reports that 33-year old Wayne M. Hubert of O’Fallon entered the plea Thursday to charges of involuntary manslaughter and endangering the life of his 6-year old daughter.  A complaint says Hubert strapped 23-month old Nathan into a car seat last June in a vehicle parked in his driveway.  Officials say he went into his home, drank alcohol and passed out.  The mother later came home and the child was found.  The coroner’s office said the boy’s body temperature was 104.6 degrees.  Hubert faces four years in jail and two years of supervised release.