By CBS3 Staff

COLLEGEVILLE, Pa. (CBS) — A 13-year-old boy has been charged with shooting and killing his 12-year-old sister inside of their Collegeville home on Larchwood Court Friday.

The DA says the children’s mother asked the boy to get her legally-registered handgun out of her car. Surveillance video shows the teen entering the home with the gun, and pointing it at his sister.

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The gun then discharged and the girl was struck in the chest and killed. She was pronounced dead at the scene.

Now, the family is trying to wrap their minds around losing a loved one that had her entire life ahead of her.

“It just sounded like a big bang,” neighbor Gia Krystopa said.

“It’s terrible,” a neighbor said.

Neighbors say a number of children live in the home. The district attorney’s office says family members were present when officers arrived on scene.

Investigators paid particular interest to the trunk of a black SUV parked out front, and evidence bags were taken from the home.

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“I feel terrible for the family. I’m a mother, I have kids. I can’t believe it,” Krystopa said.

The Montgomery County coroner removed the body nearly four hours later, as loved ones gathered in front of the home.

Krystopa, whose children play with the victim and her siblings, has a message for her neighbors.

“Anything that you need, anything that you need, we’re all here for you and we all support you. We are so sorry that this happened,” she said.

Neighbors say the victim was a student at the Spring-Ford School District.

Now as neighbors rally, sending their support to the child’s family, they’re also grappling with having to explain the severity of this tragedy to their children.

“Accidents happen and that’s so important to know that these weapons are dangerous and accidents are sometimes fatal,” Krystopa said.

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The 13-year-old has been charged with third-degree murder.

CBS3’s Alecia Reid contributed to this report.