2-year-old unintentionally shoots and kills his 11-year-old sister

11-year-old Jamara Stevens, of Philadelphia, Pennsylvania, and her three siblings, a 14-year-old boy, 7-year-old girl and 2-year-old boy found an unlocked, loaded .357 caliber handgun on top of the refrigerator in their home.  The gun had been left there by their mother's boyfriend.

The children brought the gun upstairs.  At some point, the 2-year-old picked up the weapon, pointed it in Jamara's direction and pulled the trigger.  Jamara was shot in the chest, the bullet hit her heart.  She was taken to the hospital where she was pronounced dead.

Police determined the 2-year-old boy pulled the trigger because he had traces of gun powder and a burn from the blast on his arm.

Police say this is not the first time they have been called to Jamara's home and that her mother is not cooperating with the investigation.  Police are still investigating and no charges have been filed yet.