The longtime top watchdog for Illinois’ troubled child-welfare system — who’s been highly critical of the agency’s former director leading up to his resignation amid a corruption scandal last year — is now being replaced by Gov. Bruce Rauner.

Gov. Bruce Rauner announced last week he’s appointing a replacement to Denise Kane, who was the first-ever inspector general for the Illinois Department of Children and Family Services.

“We are grateful to Dr. Denise Kane, DCFS’ first ever Inspector General, for her 24 years of public service,” Rauner spokeswoman Rachel Bold wrote in a statement Thursday.

Kane’s colleagues in the child welfare system are calling her tenure as “effective,” “fearless,” and “tenacious.”

The change in leadership comes after Kane published what will be her final annual report of DCFS, which included a biting critique of former Director George Sheldon’s leadership. Sheldon resigned last year under the cloud of a corruption investigation by Kane’s office into contracting and hiring. He was also facing questions about the death of 17-month-old Semaj Crosby, whose family had repeatedly been investigated by DCFS before her body was found under a couch in her Joliet home.

In the same report, Kane wrote that around the same time she was investigating Sheldon, DCFS contended she was overstepping her boundaries.

“It is no coincidence that this resistance came at a time when the Office [of] the Inspector General was investigating corruption cases within the former director’s management,” Kane wrote. “Optics, not reality, had become the operating premise of the organization.”

Kane, however, credits Beverly Walker, the new DCFS director, for “reversing that trend.”

When asked if Kane’s biting report played a role in Rauner replacing her as DCFS’ watchdog, Rauner spokeswoman Rachel Bold responded, “It did not.” Kane’s term expired this year, after she served for governors from both parties over five administrations.

Kane herself would not comment for this story.

Year after year, Kane’s annual DCFS report detailed the circumstances under which children and young people died, including when their families had had contact with child welfare investigators for abuse or neglect. In 2013, a joint WBEZ/Chicago Sun-Times investigation relied on Kane’s annual reports to find that more children had died from abuse or neglect — even after the agency had been involved with the family — than in previous years.

Rauner appointed Meryl Paniak to replace Kane as DCFS’ inspector general, effective on Tuesday. A DCFS spokesman said Paniak has served as the agency’s Ethics Officer and is the chief counsel for the Office of Legislative Affairs. Paniak has also worked as a psychiatric social worker, child welfare worker, and a private therapist for victims of domestic violence.

Those who work with the child welfare system said Kane’s work as inspector general has improved conditions and practices for vulnerable children, despite its series of short-term agency directors.

“I think over time she has gotten workers, the department to think about issues differently, but then you end up with a new administration and you’re starting over again,” said Anita Weinberg, director of the ChildLaw Policy Institute at Loyola University’s law school. “So it’s a constant challenge.”

A top Democratic lawmaker who chairs the House committee tasked with approving the budget for DCFS also praised Kane’s work.

“She was the proverbial bulldog in this job,” said State Rep. Greg Harris, D-Chicago, who chairs the Appropriations-Human Services committee in the Illinois House. “I was impressed every time I met her with the ferocity that she went after abusers with, and how she would not leave a stone unturned in her investigations wherever the investigations led.”

Ben Wolf, an attorney with the ACLU, which has monitored Illinois’ child welfare system for decades and has taken the agency to federal court, said he recently relied on a report from Kane showing chronically excessive caseloads for DCFS workers.

“I never doubted for a moment that her heart was focused on the best interest of the children and not on anything else,” Wolf said.

Paniak “has a very good and strong reputation and I hope will continue to do a lot of the kinds of important things Denise Kane has been doing,” said Bruce Boyer, the director of the Civitas ChildLaw Clinic at Loyola. “But she’ll be missed.”