WHEELING, Ill. (WLS) -- A northwest suburban school is dealing with the loss of a beloved teacher and athletic trainer on Monday.
Bob Gillen was killed in a crash in Wheeling early Sunday morning.
Gillen walked the halls of Wauconda High School for 27 years. By day, he taught math. His evenings, though, were spent as the school's athletic trainer, a commitment acknowledged by everyone who knew him.
"Just the hours that he worked. I cannot get over that, looking back," said former student Shay Hughes.
Hughes was a geometry student of Gillen's at Wauconda High School in 2004. But, Hughes said, it's the countless nights Gillen spent supporting the student-athletes of Wauconda that stand out. Gillen was even named Gatorade Athletic Trainer of the Year in 2017.
"For a significant period of time, while at Wauconda High School, he was the sole athletic trainer. I mean, that means he's there for every practice, every home contest," Hughes said.
Flowers adorned the entrance to the athletic training room inside Wauconda High School on Monday.
"After teaching all day long, he would come in here, and put in four or five, six, seven hours, depending on what we will have going on," Wauconda High School Athletic Director Mark Ribbens said.
It's now an empty room, echoing the pain of the students and faculty, as they grapple with the unwanted reality that a beloved teacher will never walk through the doors again.
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Police said the 53-year-old trainer and teacher was killed on East Palatine Road.
According to investigators, a suspected drunk driver was traveling with a passenger when they drove into the wrong lane of traffic, hitting Gillen's vehicle head-on.
Gillen died at the scene. His wife, Debbie, was seriously injured. Gillen's father said she suffered broken ribs, and is now out of the hospital. The suspected drunk driver was also hospitalized.
Meanwhile, the elder Gillen is still coming to grips with the loss of his son.
Ed spent his career as a civil engineer. He fondly remembered when Bob first told him he wanted to go to school to be a teacher.
"Well, everybody liked him," he said. "I was surprised that he wanted to teach math. But, I didn't think he was that good, but he was. Surprised me."
Gillen's death is a tremendous loss for his family and the Wauconda community.
"He's a great guy. He'll be dearly missed, but he would want us to move forward and continue to support the student athletes and students here at Wauconda," Ribbens said. "He was just a caring, dedicated -- just an employee that meant so much to this school and the school community."
Wauconda High School will host its first basketball game since Gillen's passing on Friday. There, ABC7 is told, they'll recognize his significant contributions.
"He had a huge impact on our kids who are here in the building right now, but our kids' older brothers and sisters, to some extent our kids' parents," Wauconda High School Principal Dan Nicholas said.
That support is coming in the form of grief counselors made available at the school for anyone who might need them.
Wheeling police are still investigating Sunday morning's crash. At this point, no charges have been filed.