CHICAGO (CBS) — On Thursday, JoAnn Cunningham will be sentenced for the murder of her 5-year-old son, AJ Freund.

The Crystal Lake mother pleaded guilty to first-degree murder in AJ’s death. AJ’s father, Andrew Freund Sr., is also charged.

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AJ’s disappearance gripped the nation when he was reported missing by his father on April 18, 2019.

Police and prosecutors have alleged AJs parents forced him into a cold shower as punishment for soiling his clothes and severely beat him on April 15. His father later found him dead in his bed at their home in Crystal Lake and buried him in a shallow grave, investigators said.

That was three days before AJ’s parents falsely reported him missing, prosecutors said.

For days, the community prayed AJ was alive. But the senior Freund led investigators to AJ’s body a week after reporting him missing. Wrapped in plastic and buried in that shallow grave in a field in Woodstock, AJ was found to have died from blows to the head.

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Just seven months ago, Cunningham granted CBS 2 Investigator Brad Edwards the only in-house jail interview:

Edwards: “DCFS paints a horror show of what went on in that house. Was it a horror show, what was going on in that house in the end?”

Cunningham: “No, we were a good, loving family.”

Edwards: “JoAnn, a lot of people are just going to have a hard time believing that.”

Cunningham: “I’m sure they do, but I don’t care what they think.”

In the interview, Cunningham denied that she killed AJ.

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Watch above for a CBSN special presentation, “The Murder of AJ Freund,” with a look back at the gruesome case, and a look forward.