The Illinois Auditor General’s office is faulting understaffing at the state’s child welfare agency for a massive backlog of cases of suspected child abuse or neglect. The office also said yesterday that the agency often failed to follow its own protocols for investigating cases and filing timely reports. The audit report shows the Department of Children and Family Services as overwhelmed by a growing volume of cases with pressure to close cases quickly. The Illinois House ordered the audit in June 2017.