Updated 11/17/11 – 5:47 a.m.

WAUKEGAN, Ill. (CBS) — A 25-year-old former daycare worker faces a long stretch of prison time, following her conviction in the death of a 16-month-old child left in her care.

As WBBM Newsradio’s Bob Roberts reports, the Lake County jury deliberated for about seven hours before convicting Melissa Calusinski of the first-degree murder and aggravated battery of Benjamin Kingan.

LISTEN: WBBM Newsradio’s Bob Roberts reports

The guilty verdicts mean Calusinski faces a possible life sentence for the 2009 slaying. She sat quietly as the guilty verdicts were read.

Amid the anger and tears, Melissa’s father, Paul Calusinski, said his daughter would appeal. His wife collapsed into his arms, crying so violently she shook. Melissa Calusinski herself also sobbed.

Benjamin’s father, Andy Kingan, also wept and shook his head as Calusinski was convicted, while Amy Kingan wiped tears away.

Two women jurors also cried as they left the courtroom after the verdict was read, holding each others’ hands.

Prosecutors said Calusinski threw the boy to the ground on Jan. 14, 2009, after having “issues” with the children in the room.

But even though Calusinski gave police two videotaped statements in which she admitted throwing the 22-pound toddler to the ground, at trial, defense attorney Paul DeLuca told jurors she never harmed the boy she liked and cared for at the Minee Subee day center.

Prosecutors dismissed defense claims the Deerfield boy suffered from an undiagnosed brain injury that played a role in his death.

Two pathologists called by prosecutors said they saw no signs of prior head injuries, only a recent skull fracture, severe bleeding and brain trauma.

One of the pathologists, Dr. Manny Montez, testified it would have been impossible for Benjamin to throw himself down with enough force to cause the head injury that killed him.

At trial, prosecutor Stephen Scheller reminded jurors that all toddlers accidentally bump their heads without harming themselves.

“We would be extinct as a species if a child could hit his head and die,” Scheller said at trial.

Lake County Judge Daniel Shanes revoked Calusinki’s bond, and she was remanded to custody after the guilty verdict was read. She could face life in prison when she is sentenced next year.

The Sun-Times Media Wire contributed to this report.

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