(CNN) -- The parents of an 8-year-old Ohio boy who died of cancer in 2008 have pleaded guilty to attempted involuntary manslaughter in his death.
Monica Hussing, 37, and William Robinson Sr., 40, face up to eight years in prison each; sentencing is scheduled for February 16.
"They thought the kid had swollen glands," John Luskin, Hussing's Cleveland-based attorney, told CNN on Tuesday.
From time to time, the boy's parents would notice a lump on his neck, but it would come and go and did not appear to bother him, Luskin said.
The parents never sought a diagnosis for their son, William, who was suffering from Hodgkin's lymphoma, CNN affiliate WJW reported.
They did not have much money, struggled to make ends meet and "were doing the best they could," Luskin said.
"No one recognized it ... the system here failed," the attorney told CNN. "It's obviously a sad case."
Hodgkin's lymphoma is a cancer of the lymphatic system. What causes it is not clear, though symptoms can include painless swelling of lymph nodes, persistent fatigue, fever and itching, according to the Mayo Clinic.
People diagnosed with the disease often have the chance for a full recovery.
"Even if it's widely spread, we can have a cure rate of 80%," said Dr. Otis Brawley, chief medical officer for the American Cancer Society.
"If they had just taken the child to the emergency room and said the child is sick, the staff would have taken care of the child ... Their approach is 'we figure out how to get paid later,' " he said.
CNN's Dana Ford and Miriam Falco contributed to this report.