WILMINGTON, Del. (AP) — A 17-year-old Delaware girl convicted in a school bathroom attack that left a 16-year-old classmate dead was sentenced Monday to six months in a juvenile facility.

The girl was convicted of criminally negligent homicide by a Family Court judge in April in the 2016 death of Amy Joyner-Francis.

Cellphone video of the attack shows Joyner-Francis struggling to fight back and escape as she is repeatedly hit and kicked in the head while her assailant holds on to her hair.

The convicted teen will be sent to a secure, residential treatment program for juvenile delinquents. After her release, she will face additional court supervision and programs until age 19, followed by two years’ probation. She also must perform 500 hours of community service.

A 17-year-old co-defendant who was convicted of conspiracy for helping plan the attack and was seen on the video kicking Joyner-Francis while she was on floor was sentenced to 18 months of probation and 300 hours of community service.

A third defendant was acquitted of a conspiracy charge.

None of the defendants testified at their April trial. The Associated Press is not publishing their names because they are juveniles.

Family Court Judge Robert Coonin in April agreed with prosecutors that the fatal encounter was an “attack,” not a fight.

An autopsy found that Joyner-Francis died of sudden cardiac death, aggravated by physical and emotional stress from the April 2016 fight at Howard High School of Technology in Wilmington. The girl had a rare heart condition undetected by her doctors.

Defense attorneys argued that her death was unforeseeable.

“This is an extraordinarily difficult case, and it has been from the beginning,” Coonin said Monday, adding that “everyone has lost.”

“The community has lost, the defendants and their families have lost, and most importantly, Amy’s family has lost,” said Coonin, who criticized social media’s effects on modern society, saying it filters out emotional cues that come from personal interaction.

He told the girl convicted of homicide that social media had interfered with developing an “appropriate sense of humanity” and allowed her to put ego ahead of thoughts and feelings about the well-being of others.

Coonin prohibited both defendants from using social media while serving their sentences.

Neither girl spoke in court. Both submitted written statements to the judge, but the statements were not read in court.

Prosecutors traced the conflict to an online group chat the day before the attack, when Joyner-Francis had offered advice to a friend about a problem involving a boy, telling her friend to “just be careful.” Joyner-Francis warned that someone might “switch up,” or betray another person. A police detective said the assailant thought Joyner-Francis was talking about her as the possible traitor.

A Snapchat posting by one of the defendants that same day shows Joyner-Francis talking to her alleged assailant in the bathroom, purportedly to try to defuse the situation. The posting notes that the girl later convicted of homicide was “bouta fight her,” followed by several emojis indicating that a person was laughing so hard she was crying.

In a victim impact statement read by prosecutor Phillip Casale, Joyner-Francis’s mother urged the judge to sentence her attackers to prison.

“It will be a disgrace … if these two girls do not serve time for the crime they committed,” the letter read.

The family declined to comment after the sentencing.

John Deckers, an attorney for Joyner-Francis’ assailant, urged Coonin to impose a sentence affirming that actions have consequences but keeping with the Family Court’s focus on rehabilitation, rather than punishment.

“We are not the worst thing we’ve ever done in our life. … Children should not be judged based on the worst things they’ve ever done,” Deckers said.

Noting that Delaware has no lock-down facility for juvenile girls, Coonin declined to send the girl to an out-of-state prison. He concluded, however, that she should serve time in a restricted-access residential setting.

“Words alone cannot ever undo the permanent damage and the hurt that you’ve done,” he told her.

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