A Pennsylvania mother discovered that her son had been dead for four days, when she sensed foul odour coming from the room where he was stationed, local newspapers have reported.
An autopsy was under way on Monday and the boy's father remained jailed in the case, reports say.
The 8-year-old boy, recognized as Jarrod Tutko, Jr., was among five children in the family who were suffering from either medical or developmental problems, the Harrisburg Patriot-News website reported.
The boy was being cared for by his father in an upper room in their Harrisburg home while his mother, Kimberly Tutko, looked after his 10-year-old sister, who is comatose, on another floor, the Patriot-News website said.
Since the parents were not satisfied by services provided by nurses, the two agreed on a division of labour. Kimberly would care only for the 10-year-old blind, deaf, bedridden daughter, who is in a vegetative state. And Jarrod Sr. would solely care for their 9-year-old Jarrod Jr., who was diagnosed with Fragile X syndrome when he was just 11 months.
The mother had no idea that her son had died last week, isolated in a faeces-covered room, until she was alerted by strange odour. She had not seen the boy –who was prone to smear faeces on himself, in four years because she was afraid she could carry infections back to his sister, the news website reported.
The boy's mother called police on Friday night after she asked her husband about the peculiar stench coming out of the upper floor where the boy was stationed. The husband told her that their son was dead before he brought the decomposing body from the third-floor bedroom, the police have said.
On Monday, Kimberly Tutko told the news website that until the incident occurred, she thought the arrangement had been working perfectly well.
"Up until this point, what just happened, everything was fine," she was quoted as saying. "There were no problems, exclusion this last week, depending on when (Jarrod Sr.) started to let that room go."
The 38-year-old father was being held on a $500,000 bail on charges of child endangerment, concealing the death of a child and abuse of a corpse.