She said the boy never complained about his neck.
"He played, he went outside, he wrestled, he played video games," the boy's sister said. "He was the happiest kid you could imagine. It never seemed like he was suffering."
The emotional aftermath from their son's death led the couple to split, according to Luskin.
The couple's four other children under 18 were placed in the custody of a family member. Luskin said Lillian Hussing, upon turning 18, decided to return to live with her mother.
Rein said Robinson agreed to plead guilty so his children could be spared any further grief and wouldn't have to suffer by testifying. Lillian Hussing said her mother took a plea bargain because of the uncertainty of a trial and fear she could be sent to prison for a long time.
As part of the deal, the prosecution agreed to drop four counts each against each parent, including child endangering. Prosecutors didn't agree to a sentence recommendation. Both Luskin and Rein had said they hoped the judge would consider probation.
"There's not a day my client ... starts without shedding a tear for his son," Rein said.
The coroner ruled that the boy was a victim of medical neglect and died from pneumonia due to Hodgkin lymphoma.
Hodgkin lymphoma is a highly treatable cancer, with as many as 95 percent of patients in early stages of the disease surviving for five years or more with treatment. It's one of the most common forms of cancers among children.
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