Quinton's mother, Leilani Simon, reported her son missing on October 5 and claimed his father kidnapped him. Police determined the boy's father was not involved in his disappearance and named Leilani as the prime suspect in the case.
A week later, police announced they had evidence that Quinton was dead and began searching a nearby landfill for his body.
On Friday, they found human remains and believed they belonged to Quinton. They have been sent to the FBI lab in Quantico, Virginia, for confirmation.
Leilani was taken into custody and is facing charges of malice murder, concealing a death, and false reporting/making false statements.
Officials did not say how the young boy died.
"This is a heartbreaking development for everyone who loved Quinton. For the many people who came to know him after his disappearance and for our department. When we first received the call that Quinton was missing, we were hopeful that we would find him alive and unharmed, but as we have been telling you for weeks, all of our evidence pointed to his mother being responsible for his death and disappearance, and his remains being found in the landfill," Chatham County Police Chief Jeffrey Hadley said during a news conference.