The investigation began back on August 6 when Washington Township officers were called to a dispute inside an apartment on Woodmont Circle.
According to court documents obtained by Action News, the victim, identified as 80-year-old Florence Dicriscio, told officers that her daughter struck her several times with a broomstick.
Dicriscio was initially transported to Jefferson Washington Township Hospital for her injuries. She later died on August 9.
The victim's daughter, 65-year-old Loretta Barr, was initially charged with assault. After her mother's death, charges were upgraded to manslaughter.
An autopsy conducted on August 10 ruled Dicriscio's cause of death to be blunt force trauma to the body and head. The manner of death was ruled homicide.
Authorities have not said what sparked the dispute.
Barr is being held at the Salem County Correctional Facility.