Police were at a loss to explain why a man shot and killed his wife and his 17-year-old son, then shot his 15-year-old daughter in the back as she ran from their home in Robbins with two other children.

As a 14-year-old boy and his 5-year-old nephew kept running, Michael Worsham dragged the girl back into the home and fired at witnesses who had stopped their car, according to Robbins Police Chief Mitchell Davis. The children and the witnesses were not hit.

Inside the home, police found Worsham, his wife of 12 years, Michelle Ollie, 42, and their two children, Steven, 17 and Trisdion, 15. Ollie and the teens were shot to death, and it appeared Worsham may have died from a heart attack, police said.

"I cannot imagine what could bring someone to such a dark place where they believe they need to take the lives of his whole family," Davis told a news conference this morning.

He praised the quick actions of the 14-year-old, who alerted his sister to the shooting while struggling with Worsham, then grabbed his nephew and ran. "That 14-year-old is a hero," Davis said.

The shooting happened around 10:30 p.m. Sunday in a small brick home on the 13600 block of Pulaski Road in the south suburb. "For reasons unexplained," Worsham shot his 17-year-old son in the kitchen, then went upstairs and dragged his wife out of bed and shot her, according to Cook County Sheriff Tom Dart.

The 14-year-old heard a "pop" and came downstairs and "saw his brother lying dead on the floor," Dart said.

"The 14-year-old stated that he attempted to wrestle the gun away from his stepfather, but his stepfather told him if he stopped fighting him, he could leave," Davis said. The boy yelled out to his 15-year-old sister and grabbed his nephew and all three ran out of the house, police said.

But Worsham then fired and hit the 15-year-old and she collapsed on the front porch, police said. "As they're all running out of the house, she was the last to leave and was shot," Davis said.

Davis and Dart said the shooting apparently stemmed from a domestic dispute but they could not exactly say what sparked it. He said police had not been called to the home before.

Police got a call of shots fired at the house around 10:40 p.m. Sunday. Officers were met by a witness who said she had seen someone, apparently the girl, shot at the home.

The officers saw a trail of blood outside the front door and requested assistance from surrounding police departments and the sheriff's office, police said in the statement. The home was surrounded and, after trying to contact someone inside, officers forced their way in, police said.

"It's a mess over there," Dart said at the news conference. "Horrific, seeing a very tiny house covered in blood ... We're really struggling with how did something like this escalate to this point?"

Police said Worsham had a valid Firearm Owners Identification card and worked as a security guard for the Thornton School District. His wife was a childcare worker at a teen shelter, relatives said.

Worsham had been hospitalized around six months ago for an illness, possibly heart-related, according to his second cousin, Toni Gardner.

Gardner lived across the street from the couple. On Sunday morning, they had stopped by for coffee, a weekly custom, and they had been in high spirits. Michelle was planning to make hot wings for the Super Bowl that evening and Worsham was talking about getting out a snow blower, Gardner recalled.

"He was a big cream puff," she said. "There was no sign of anything. No physical abuse, no psychological abuse, that anyone knew of. "We don't know what triggered any of this.

"After they do all their forensics and their investigating, I'm sure they will say he was some kind of monster, but he was not a monster."

The couple had been friends since childhood and had been married for more than 10 years, a period that came after several breakups.

Michelle worked overnight shifts as a childcare worker at a teen shelter across the street from their house. Gardner worked there as a cook on the day shift. At home, Michelle, who was "a little 4-footer," ran the household and was a devoted wife and mother, Gardner said.

Ollie and her daughter Trisdion were pronounced dead at the scene. Worsham and his son Steven were pronounced dead at Metro South Hospital. Ollie and the children all suffered gunshot wounds, police said, but Worsham did not. Police said he may have suffered a heart attack.

The 14-year-old boy was placed with an aunt, and the 5-year-old was taken to his mother.

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