There, Justin Davidson's mother saw a Facebook message posted by her son that was both strange and suspicious.
"Might be moving :(," it read, according to law enforcement sources speaking to the New York Post.
Alarmed that her son might be involved, the mother contacted police, who searched the boy's home and found Autumn Pasquale's bicycle along with some of her belongings.
On Monday night, authorities recovered Autumn's strangled body in a recycling bin in a house next to where Justin, 15, and his brother Dante Robinson, 17, live with their mom, stepdad and an 18-year-old brother.
The two boys were charged Tuesday with murder and conspiracy to commit murder, while Justin was charged separately with luring. Autumn and Justin, who lived 17 houses apart, around the corner from each other, were Facebook friends.
Because the boys are minors their names have not been officially released by prosecutors. But they were identified by sources to multiple news outlets.
Town in ShockIt was a shocking twist in a case that had residents on edge. Before the arrests, Autumn's great-uncle, Paul Spadafora, told reporters: "There's evil everywhere, even in the small town of Clayton."
Police now say they believe the younger boy lured Autumn – last seen riding her white BMX bike with maroon handlebars – into the house with the intent to steal her bike for parts, then killed her with the help of his brother.
"I think someone wanted the girl's bicycle," the boys' estranged father, Alonzo Robinson, tells the Newark Star-Ledger. "Maybe she wanted her bike and resisted, and one of them snatched her off a bike."
The medical examiner said Autumn died of "blunt force trauma, consistent with strangulation." She had not been sexually assaulted, reports New York's Daily News.
Addressing police and volunteers who aided in the search in the blue-collar community 22 miles south of Camden, Spadafora said: "We believe she is where God wanted her to be. So the ending here is sad, but for the relatives that have greeted her in heaven, it's a happy day."
Said Clayton Mayor Tom Bianco: "It's shocking. A 12-year-old girl won't be able to celebrate her 13th birthday. Her mother and father won't be able to kiss this girl for the rest of their lives. They've been robbed of themselves."