In exclusive interviews with PEOPLE, Ryan Mangan's parents are now opening up out about his young life and his sudden killing by another teenage boy in 2015

A part of George Mangan Jr.’s home has remained almost unchanged for more than two years: the bedroom of his 16-year-old son, Ryan Mangan, who was shot and killed by a friend in February 2015.

The case made national headlines — not for how Ryan died but because of what the other teenager, Maxwell Morton, did afterward: snapping a smiling self-portrait in front of Ryan, slumped and bleeding, after he had been shot.

Morton, who was also 16 at the time, then fled the scene with the gun, leaving Ryan dying as his lungs filled with blood. Morton later sent his selfie to another boy online. He did not call for help.

After he was killed, Ryan’s parents declined to comment as Morton’s prosecution proceeded. But in exclusive interviews with PEOPLE, they are now opening up about his young life, the shooting that cut it short and the grief they have carried ever since.

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From left: George Mangan Jr. and Rebecca Murtland hold up a photo of their son, Ryan Mangan
| Credit: Ross Mantle

• For more from Ryan Mangan’s parents on his life, death and the court case that followed, subscribe now to PEOPLE or pick up this week’s issue, on newsstands Friday.

In May, Morton was sentenced to at least 15 years in prison on a third-degree murder charge for killing Ryan, with his photo at the scene used as key evidence against him. Morton was tried as an adult and convicted days after the two-year anniversary of Ryan’s death.

Prosecutors unsuccessfully sought a more serious charge of first-degree murder, but Morton maintained the shooting was a tragic accident as the pair played with a gun. (His lawyer is appealing.)

“It was like my son died all over again a second time,” George says of the verdict. “And I just feel that this isn’t justice for him.”

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Ryan Mangan
| Credit: Courtesy Rebecca Murtland

Both George and Ryan’s mom, Rebecca Murtland, attended Morton’s murder trial, where the photo of their dying son was shown to the jury. They dispute how close he really was with Morton.

“They had two years to rehearse a story,” George says of the defense, adding, “They had to have an excuse for every little thing.”

Rebecca agrees. “No trial is fair when the victim cannot participate,” she says. However, speaking about Morton’s sentencing, she says she is “thankful the judge realized the audacity of the crime.”

Family and friends remember Ryan, a high school junior, as a naturally gifted student and a well-liked teen who loved animals, basketball and video games.

His dad says he grew up always “by my side, wanting to help or be there.” In the summer, he and his mom were “water park enthusiasts.” He worked at McDonald’s and he volunteered at the Red Cross. His parents were teaching him to drive.

“Ryan deserved justice,” Rebecca says. “He could have been saved.”