HARTFORD, Conn. -- A Department of Children and Families employee is out of a job after a baby died in foster care in May.

The 7-month-old baby died after being in the care of Suzanne Lestro, 42, in her Mansfield home for a week. The baby, Michael Brown, was rushed the baby to Windham Hospital then Hartford Hospital, where he died.

State police said the doctor could tell the baby didn't fall off a bed as Lestro had said because his head injuries were too severe. The medical examiner confirmed this.

Lestro was charged Wednesday.

Susan Hamilton, commissioner of the department, held a news conference Thursday about the baby’s death and discussed the process used for Lestro’s licensing and announced that at least one person would lose their job.

“I found that the quality of the investigations was substandard and unacceptable,” Hamilton said.

After the baby died, Hamilton told staff to investigate the incident and review how it happened. Staff learned of two previous investigations of Lestro in 2006 and 2007 alleging abuse.

Of the DCF investigators who handled past allegations of abuse against Listro, one has been fired, another investigator and a manager are being investigated and another manager has been suspended, Hamilton said Thursday.

When Listro was licensed to be a foster parent, the licensing examiners weren't told about those past allegations, Hamilton said.

“Although the allegations were unsubstantiated and would not necessarily have precluded licensure, my concern really related to making sure staff had the access to that underlying information,” Hamilton said Thursday.

Michael's first foster mother said she does not think the baby was active enough to fall off a bed.

Of 3,400 DCF workers, 28 are also foster parents as Suzanne Listro was, and 15 more have applied, Hamilton said. An outside agency will handle their licensing.

State Child Advocate Jeanne Milstein accused Hamilton of playing musical chairs, “aggressively reviewing and upholding quality care should be common sense and commonplace - not simply in reaction to tragedy.”