Pinellas County Sheriff Bob Gualtieri said a 6-year-old boy "violently killed" his 2-week-old sister when the two were left alone inside a hot car while the mother went into a store.

The mother, 62-year-old Kathleen Marie Steele, of North Redington Beach, was arrested Thursday and charged with aggravated manslaughter. She is scheduled to make a first appearance in court Friday.

  • Mom, 62, arrested after death of newborn daughter
  • Sheriff said 6-year-old brother beat baby to death
  • Happened while mom left kids in car alone for 30 minutes, sheriff said

Gualtieri said Steele left the baby, also named Kathleen, alone in a vehicle with the 6-year-old and another child, age 3, while she went into a cell phone store in St. Pete on Monday, August 8.

Baby Kathleen started crying. According to reports, her cries are what prompted her brother to beat her to death.

"The way he was describing it, he was tossing that baby around like a rag doll,” said Gualtieri. "Her appearance was one of just a kid that had been pummeled."

The sheriff said the children were left in the vehicle with the doors locked and windows up for 30 minutes.

When Steele got back to the car, the 6-year-old told her baby Kathleen was hurt but she apparently ignored him.

After they got home, she called a neighbor who then called 911. But it was too late, the baby was already dead. The sheriff explains her mother's reaction.

"Deputies are there, paramedics are there working on a 13-day-old baby who's obviously dead,” said Gualtieri. “And she turns around and goes into the kitchen and starts putting groceries away, who does that?"

Steele was the baby's biological mother. Gualtieri said Steele was artificially inseminated with her dead husband’s sperm.

The 6-year-old is so young that he is not being charged. Gualtieri said the boy did show some remorse.

"At one point he did make a statement, something to the effect of 'sometimes people make really bad mistakes,'" he said.

The two children have been placed in the care of Department of Children and Families.

The sheriff says Child Protection Investigators were called to look into the family a couple of times in recent weeks. There was a complaint to a hotline that the children weren't being supervised properly, but he says investigators found no evidence of that.

He also says Steele had the baby unbuckled in a carrier and she fell out on the stairs. She took her to the hospital but investigators thought that was an accident.

We're told the 6 year old was a first grader at Lakewood Elementary School. The district's superintendent, Dr. Michael Grego, released this statement saying "This is a heartbreaking situation. The death of a child, of an infant, is so hard to process. I am deeply saddened by this...We will have support teams for our students and staff. And continue to work closely with the sheriff."