24-year old Josephita Brown was arrested Thursday night after her daughter Seanita died at Chhildren's Hospital of Philadelphia on Tuesday.
The girl lived on the 2200 block of South 56th Street.
Police say she suffered from a lacerated liver caused by blunt force trauma. Officials say she was bleeding from her ears and covered with bruises.
"It just frustrates you and leaves you with the feeling of dismay that a poor defenseless child would die at the hands of the person who is ultimately tasked with protecting them," said Deputy Police Commissioner Richard Ross.
Brown was arraigned Friday morning and is being held without bail.
Police say her boyfriend remains in custody, but so far he has not been charged.