Her mother wasn't waking up, the 15-year-old girl worriedly told a neighbor on Thursday morning.

Karen Moore wasn't asleep, though. She was dead. And Braselton Police say the teenage daughter who initially feigned innocence later admitted to shooting Moore, a first sergeant and recruiter in the U.S. Army, in the back of the head Wednesday evening as her mother sat on the couch facing the television.

Moore's husband and son, both Army reservists, were stationed in Alabama and were not at the family's two-story brick home in Braselton. Moore's death was not only a grievous loss for loved ones. It was a loss for the community and the nation, police said Friday.

"It's very tragic," said Assistant Chief Lou Solis of Braselton Police. "It affects family and friends, but it also affects the community because now you've lost a great person that serves the country."

The 15-year-old, whose name was not released because she is a juvenile, was being held Friday night at a youth detention center in neighboring Gwinnett County on a murder charge. It was not immediately known whether she would be prosecuted as an adult.

Barrow County District Attorney Brad Smith did not return calls seeking comment Friday.

The girl told police that she had argued with her mother before the shooting. One point of conflict brought up during the disagreement was the teen's relationship with 17-year-old Christopher Nieves, whom she referred to as a friend, Solis said.

However, both youngsters allegedly admitted they had sex sometime in the night after the 15-year-old allegedly shot her mother.

Police said the 15-year-old invited Nieves over to her home on Sahale Falls Drive and he may not have been aware of the violence that preceded his arrival. The two had only known each other since January, Solis said.

The pair apparently contemplated leaving the house. Neighbors say they saw two teenagers trying to push a blue Volkswagen Beetle convertible that would not start. Inside the vehicle, investigators found the gun believed to be the murder weapon along with Moore's purse.

"I saw the car in the road and it wasn't in the driveway," said Lauren Mathison, who lives down the street. "And they were trying to push the car in the driveway. "

Thursday morning, the 15-year-old asked a neighbor to jump-start the car and then told the neighbor that she couldn't get her mother to wake up, Solis said.

Police have not charged Nieves in connection with the shooting. However, he was arrested on a statutory rape charge since the girl is a minor. Nieves was being held at the Barrow County jail Friday awaiting a bond hearing.

A woman who answered the door at Nieves' Sugar Hill apartment and who said she was his mother was shocked to learn her son had been arrested. She said her son had never been in trouble. She said she was under the impression the girl he was dating was "16 going on 17." The woman declined to give her name and cut off the interview.

Moore, 42, was an active-duty soldier who worked as a recruiter for the U.S. Army station in Athens, Solis said. Her adult son declined to talk to a reporter when approached outside the home on Friday. He said his father was at the Braselton police station.

Solis said the case has been difficult for investigators, many of whom are former military officers.

"Last night, Dad made a comment, if that didn't touch you ... " said Solis, his voice trailing off. "After we got done talking to him around 4 a.m., the thing the dad told me, he looked right at me and he said, ‘I love my daughter.'"

Brian Karr, who lives two doors away from the Moores, said he didn't know the family well. But he knew they were a military family, because he often saw the parents and son getting in their car wearing fatigues. He also spotted Moore walking with her daughter around the neighborhood many times, laughing, talking and seemingly enjoying one anothers' company.

"They seemed like a very happy family," Karr said. "That is what has me baffled. ... You would think if she was on a tour of duty somewhere is where she would be worried [about her safety], but not in her own home."