CHICAGO (CBS) — Four days after he was shot in the head by a disgruntled colleague, a Loop executive remained in critical condition on Monday, but a family spokesperson said he was showing some improvement.

Steve LaVoie, 54, was shot Thursday morning at the LaSalle Street offices of ArrowStream, a technology firm he founded in 2000. His company had recently undergone downsizing, and chief technology officer Tony DeFrances had requested a meeting with LaVoie on Thursday to discuss his own recent demotion, when DeFrances pulled out a gun, and the two struggled before DeFrances shot LaVoie in the head and abdomen, then took his own life.

LaVoie remained in critical condition Monday morning at Northwestern Memorial Hospital, according to a hospital spokesperson.

A family spokesperson who has been providing updates on LaVoie’s condition on the CaringBridge website, posted Sunday that Lavoie has shown “some small improvements in natural reflexes.”

LaVoie is married with three children. His wife, Jody, has been at his side at the hospital, but has said she is not ready to speak publicly about the shooting.

Family spokeswoman Sue Michalowski has provided brief updates on his condition each day since the shooting.

“The swelling in his brain remained consistent with yesterday,” she wrote Sunday afternoon. “He seems to be resting peacefully. Jody has been reading all of the well wishes to him and she is certain that is helping to give him strength. Please continue your prayers.”

LaVoie’s CaringBridge page has been visited more than 12,000 times since the shooting, and hundreds of messages of support for him and his family have been shared on the site.

Friends and colleagues have said LaVoie and DeFrances were longtime friends. According to the ArrowStream website, DeFrances had been with the company “virtually since its inception.”

George Volland, who knew DeFrances, expressed shock about what happened.

“Tony was a great guy,” he tells CBS 2. “I knew he was very dedicated in his job. He’d always have his PC with his backpack, and he’d always be working on the train. It was just a complete shock to me. I’m shaken, frankly.”

“I really liked the guy, and to hear this is just a total shock. He must have snapped,” Volland added.

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