The woman was detained by homicide detectives and taken for questioning on Wednesday night.
Little Jeniece died on the night of November 24, at the San Fernando General Hospital.
Police were told that she became ill after eating a meal of French fries prepared by a female relative.
The child’s father, Robert Figaro, had left the child in the care of the relative and when he returned home his daughter was in an unconscious state.
Little Jeniece taken to hospital, but pronounced dead by doctors.
Her autopsy was performed four days later, and it was discoverede that she died from a beating to the head and abdomen.
Investigators believe the child was being abused for months.
Jeniece’s father said he was not aware that his daughter was being beaten.