Trebel carries the photo, he said, so he doesn't forget.
"As time passes, it's hard to remember his laugh or the sound of his voice," he said."But I'll never forget his bravery."
Trebel held the photo close to his heart Sunday morning as the sound of taps drifted across Cedar Lawn Memorial Park.
It was a simple gesture, but a moving one.
"It's the thank you he never heard," Trebel said.
About 100 people said "thank you" to the men and women who have sacrificed their lives for their country during the annual Memorial Day service at Cedar Lawn.
The guest speaker was Sen. Donald F. Munson, R-Washington, who told the crowd, "It is the military, not the reporter, that has given us freedom of the press.It is the military, not the poet, who has given us freedom of speech. It is the military, not the campus organizer, that has given us the freedom to demonstrate."
During the ceremony, Munson honored Boonsboro resident Robert E. Glausier, a retired captain with the U.S. Marine Corps who served from 1949-70 and earned a Battlefield Commission.
Presenting Glausier with a medal, Munson said, "He is a true hero, one of the reasons I am a senator in a free society."
Munson said the medal, which features the Maryland seal, is a small thank you "for all Capt. Glausier represents and all the military he represents."
The ceremony also included the laying of a wreath by members of the American Legion Post 42 Honor Guard.
The program concluded with red, white and blue balloons being released into the air.