The Department of Defense reported Cpl. Koehler, who graduated from Milan High School in 2003, was assigned to the 1st Battalion, 8th Marine Regiment, 2nd Marine Division, II Marine Expeditionary Force, Camp Lejeune, N.C. He is the seventh Operation Iraqi Freedom casualty from the Monroe County region.

Military officials did not release a cause of death, but those close to the family believe he was shot during a mission in Al Anbar province. A trained sniper, he was part of a scout sniper platoon that was sent to the city of Haditha to help counter recent insurgent sniper attacks.

Services for Cpl. Koehler will be held in the First United Methodist Church at Washington and Washtenaw in Ypsilanti, said his father-in-law Gary Moss. Cpl. Koehler married Hillary Moss, his high school sweetheart, in the same church.

"He was a dedicated husband," Mr. Moss said. "He was serving his country and (this) just wasn't supposed to happen. His smile lit up the room. He was a great guy."

The youngest son of Ron and Mary Koehler, he also is survived by a brother, Robbie, said Kevin Hlavaty, a close family friend. Cpl. Koehler's father is a retired police captain and his mother is a nurse. They live in New Mexico and are planning on returning to Michigan soon for the funeral.

"He came from a very good family," Mr. Hlavaty said. "He was solid and decent, raised by two very wonderful, loving parents who taught him to be capable and accountable."

While at Milan High School, Cpl. Koehler was an athlete who excelled in football and baseball. His coaches described him as tenacious and a natural leader.

Upon graduation Cpl. Koehler and Mr. Hlavaty's son, Elliott, enlisted together. They were best friends and Mr. Hlavaty became close to Cpl. Koehler over the years.

"They both felt that joining the Marines would be something meaningful and would be a big challenge for them," Mr. Hlavaty said. "But Elliott came home and Gary did not."

Cpl. Koehler earned good grades and played sports for the fun of it, Mr. Hlavaty said. He said Cpl. Koehler liked to compete at almost anything, was adventurous and had a reckless side. He always had fun, Mr. Hlavaty said, but he respected his elders and his country.

Cpl. Koehler enlisted, thinking it would be a special way to contribute. He believed it was a patriotic act, Mr. Hlavaty said.

In the fall of 2004, he was shot in the leg during battle in Al Fallujah and earned a Purple Heart. He came back home in January, 2005, a changed person, Mr. Hlavaty said.

"He knew the way very few of us know what it means to serve your country in combat," Mr. Hlavaty said. "He came back not as a cut-up, life-is-about-fun kid, but as a man."

His battalion was redeployed in June as part of a Marine Expeditionary Unit and their mission was to be a ready response resource. In the last month of this assignment, Cpl. Koehler's platoon was sent to the Al Anbar province. He was killed while countering insurgent sniper attacks.

"It was dangerous and he went because it was his job, not because he wanted to go back," Mr. Hlavaty said. "After the 2004 battle in Al Fallujah, he knew what being a warrior really means. He went back because he was not one to run from his responsibility."

Mr. Hlavaty said Cpl. Koehler told him he knew that to function in that environment soldiers must accept the possibility of death each morning and get past it.

"Gary will be terribly missed for the laughs and the antics and his warm nature and his friendship," Mr. Hlavaty said. "He was like a second son."