A Florida mother charged last month with child abuse has now been charged with her 2-ear-old son’s murder.

Rebecca Louise Gussage-Johnston, 24, was initially arrested on May 19 after the toddler died from injuries he suffered a day before, when Gussage-Johnston admitted to “punishing” the boy because he was “acting out,” WESH reported.

After the Hillsborough County Medical Examiner determined the boy’s death was “a homicide due to severe neglect,” Gussage-Johnston was charged with first degree murder while engaged in aggravated child abuse.”

According to the arresting officer’s report, Gussage-Johnston said she had strapped her son into a chair for more than 15 hours and that he suffered from head trauma, bruising, and other wounds, WFLA said. She told detectives that she saw him “suffer from seizures and shaking uncontrollably” but that she did not call for help for more than 24 hours, despite having a working phone.

A concerned family member finally called 911, reporting a child in distress.

Family told WFLA that Gussage-Johnston lived in an RV with the boy, an 8-month-old daughter, and the children’s father. It’s not clear where the father was during this time, but family said the baby girl was now in the care of her grandfather.

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[Featured image: Rebecca Gussage-Johnston/Hillsborough County Sheriff’s Office]