There was indeed “something else” going on here. Previous renditions of this story have included the information that marijuana was another thing they had plenty of money for. Plus the mother’s sister offered to take the boy to a doctor, when she saw his condition, but the parents refused (that’s when the sister called social services, leading to the prosecution of the parents, but it was too late to save the boy).
http://www.cleveland.com/news/plaindealer/index.ssf?/base/cuyahoga/1236846795144490.xml&coll=2
Could it be that the parents just aren’t smart and really did think the kid would get better without doctors?