HALLANDALE BEACH, Fla. -

Dontrell Melvin was never given a real shot at life. The infant was last seen alive in July 2011 when he was just 5 months old.

In a newly-released autopsy report, the Broward County Medical Examiner Wednesday said the boy likely died a few weeks later at 6 months old.

But it took 18 months before anyone would realize Dontrell was missing. In January, police were called to the back of a Hallandale Beach home and unearthed tiny skeletal remains, which DNA tests later proved to be those of the once missing boy.

In late March, the Broward County Medical Examiner's Office ruled his death as a homicide. At the time, the medical examiner ruled Melvin died from "violence of undetermined means."

The boy's parents -- Calvin Melvin, Jr. and Brittney Sierra -- were both charged in connection with their son's disappearance. But neither have provided information as to what actually killed their son, or who buried his body.

Wednesday's report also said that there is no evidence that Dontrell died of natural causes.

The parent's other two children were turned over to DCF social workers. Brittney Sierra is pregnant again, and just days away from giving birth in jail.