For reasons having to do with establishing proof of ownership, police said, the parents were not immediately charged with possession of the weapons.
Cynthia Bennett was out of the house and her husband was in an upstairs bedroom when a gunman or gunmen burst in and opened fire on Christopher Malcolm, 17, a new father who was about to enter his senior year of high school, and his 13-year-old brother, Rohan Bennett, also known as "Sonny," who had just completed middle school.
Malcolm was shot several times and died at the Hospital of the University of Pennsylvania. Police say they believe Bennett was shot in the living room and dragged himself to the basement, where he was found dead.
Investigators theorized that the parents and the 17-year-old were the intended targets. Police sources said Malcolm had had three convictions for illegal drugs.
"At the end of the day, your 13-year-old and your 17-year-old [died] because of whatever drug nexus was going on in the house," Capt. James Clark said Wednesday at a news conference about the slayings.
Contact staff writer Michael Matza at 215-854-2541 or email@example.com.