CHICAGO (CBS) — A 24-year-old Marine from Chicago’s Beverly neighborhood has been killed in Afghanistan.

Cpl. Conner Lowry, a gunner on a Humvee, was killed Thursday while conducting combat operations in Helmand province, the U.S. Department of Defense said. The death is under investigation.

Signs of Conner Lowry’s military service are clear at his Beverly neighborhood. Sadly, so are the signs that he won’t be coming home.

“I was always just in denial that my brother would ever be killed over there.  I didn’t think it would actually happen to him,” Grace Lavin, Conner’s sister, told CBS 2’s Mai Martinez on Friday.

Thursday afternoon, Conner’s family got the visit they feared most. Three Marines explained that Conner had been killed, but offered little detail.

Grace says Conner was always looking out for her and others.

“He always wanted to serve others, so that’s why he served our country,” she says.

Sixth-grade students at Christ The King School, 9240 South Hoyne, were preparing a care package for Lowry — filled with St. Patrick’s Day cards and goodies — when they learned about his death.

“We were actually going to send him a box today that had St. Patrick’s Day cards we had made for him,” said teacher Christine McElroy.

McElroy said her son and Lowry had been friends since they were babies.

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“I know that [the students] were very proud of him,” McElroy said. “Their cards were always telling him they were praying for him.”

Lowry’s family says he was a student at the University of Iowa when he decided to join the military with some friends a few years ago. They say he’d been in Afghanistan since October.

Lavin said her son enlisted because he thought it would be good for him and would help his country.

His younger sister, Grace Levin, said her brother tried to protect her — telling her that he’d probably never see combat even though he clearly knew he would.

The Associated Press contributed to this story

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