The child’s stepmother, Heather Jones, 31, pleaded guilty in November to the same charge and is serving a life sentence in Topeka, Kansas.
The boy died sometime in September or October 2015, but his death was never reported, authorities said.
Investigators discovered Adrian's body in a pig pen while responding to a domestic disturbance call made by Heather Jones, who claimed that her husband had beaten her.
The child was “essentially starved to death,” prosecutors said, and suffered horrific abuse before he died.
Several calls were made to child welfare authorities in Kansas and Missouri as the family moved back and forth across state lines, according to the boy’s grandmother.
“He was horribly abused, neglected and ultimately killed,” former prosecutor Sheryl Lidtke said as Heather Jones was sentenced last year.
Gruesome photos and video later found on her computer showed the child being struck by a broomstick and being forced to stand in chin-high filthy water in the family’s pool. Other images included shots of Adrian’s emaciated frame and pictures of him being forced to stand outside wearing little clothing in frigid temperatures with his hands cuffed behind his back.
Maternal grandmother Judy Conway said she hadn’t been able to see the boy for months before his death. Adrian was “a gorgeous little boy” who had “the kindest heart,” she told The Associated Press.
Conway forced herself to watch the videos taken in the Jones home by more than 30 surveillance cameras.
The first time she saw them, “I physically threw up. That’s how bad it was,” Conway said. “What they did to my grandson was beyond horrific.”
In a statement released last week, the head of the Kansas Department for Children and Families said the agency “thoroughly investigated” each abuse allegation.
But the administrator, Phyllis Gilmore, did not release the number of cases or what allegations were made.
Gilmore said her department shared information with Missouri officials, and last had contact with the family in early 2012.
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