People could not stop recalling good things on Tuesday night about Douglas J. Green, who grew up in Northern Virginia and was known for caring about his high school and its students and teachers and the community that surrounded it.

He also cared about his country, and shortly after graduation from Potomac Falls High School in Sterling, he joined the Army.

Spec. Douglas J. Green, 23, was killed in Afghanistan on Sunday, the Pentagon said, when insurgents attacked his unit using a makeshift bomb and small arms fire.

“It’s pretty devastating,” said his aunt, Stacy Dinkel. “Doug was one of the nicest human beings on the face of the Earth. He was an amazing person.”

In the hours after news of his death began to spread, hundreds of people posted remembrances on a Facebook page created in his memory.

“Everybody loved Doug,” said his mother, Suni Erlanger. “Everybody loved him.”

Chad Runfola, who was an assistant principal at Potomac Falls while Green was there, recalled that he “was just so genuinely nice to others.”

He “always communicated a sense of caring for his teachers, his classmates and his school,” Runfola said.

In the eastern Loudoun County community, “this was a very special young man,” said John P. Murray, a Newspaper Association of America executive and Loudoun resident.

“He was a pretty selfless kid,” said David Spage, who was principal at Potomac Falls during Green’s years there. His ethic of service was such that “when he decided he wanted to go serve his country, it wasn’t a surprise.”

His family had tried to dissuade him from enlisting, his mother said. His maternal grandfather, Jay Chabrow, a technology consultant, said he wanted Green to work for him. But, Erlanger said, “he loved his country and nothing was going to stop him.”

Green was “my hero,” Chabrow said.

After enlisting in 2007, Green served a tour in Iraq. He was sent to Afghanistan in April as a member of the 3rd Battalion, 21st Infantry Regiment, 1st Stryker Brigade Combat Team, 25th Infantry Division, based at Fort Wainwright, Alaska.

Family members said he had played football at Potomac Falls, probably as much out of a sense of obligation to the school as anything else. He was also prominent in drama, and, his mother said, he “played the bad guy” in a school production of “Footloose.”

Many remembered Green for his sense of humor. He was “quite a character,” Spage said. His mother thought that made him something of an atypical soldier. “He was a stand-up comedian,” she said.

Even in difficult times for Green and his unit in Afghanistan, Erlanger said, “he made them all laugh.” In times of peril, she said, Green would assure his fellow soldiers “that everything’s going to be okay.”

Erlanger said her son’s enlistment was to be up before the end of the year. She said he planned to return home and marry his sweetheart, attend college, work for the Secret Service or the CIA and, perhaps, enter politics.

Other survivors include his father, Douglas Green of Sterling, and two sisters.

“You were an awesome dude,” read one comment on the memorial Facebook page. “You always knew how to make me feel better,” read another.

“You impacted so many lives with your goodness, humor, and positive attitude,” read yet another. “You had an inexplicable way of drawing people toward you.”