Alfreda Giedrojc was charged with first-degree murder in the death of Vivian Summers after she was left alone in the home with the child Sunday morning, the Chicago Tribune reported Monday.
The baby's father, Joe Summers, had left the infant at the Oak Park home of his mother-in-law while he helped his brother-in-law work on a house across the street, the Chicago Sun-Times said.
Boleslaw Giedrojc, Alfreda's husband, went across the street later to check on the project, Assistant State's Attorney Michael Deno told a bond hearing.
Alfreda Giedrojc allegedly took the baby off a couch where it was sleeping, put her on the floor and hit her with a sledgehammer, Deno said. When the baby continued to cry, she allegedly slit the infant's throat with a kitchen knife.