It happened around 10 a.m. Monday on the 2000 block of Glendale Avenue during a a church group get-together.
Police say the 14-year-old girl from Lansdale, who was visiting the home, suffered a gunshot wound to the face.
She was able to walk outside of the home as police arrived. They took her to Jefferson Torresdale Hospital in stable condition.
Chopper 6 was over the home as there was a large police response. Multiple police cars were parked outside the home and officers were walking in between the alleyways.
Investigators believe the 12-year-old boy was playing with the 14-year-old girl and showing off several firearms.
"She was in the basement with another male around the same age who was handling a weapon," said Philadelphia Police Commissioner Richard Ross.
Police say there were multiple guns found inside the home. They are looking into why the gun owners did not have the weapons locked up.
Police said they've taken two shotguns and two handguns out of the home. Two guns are still unaccounted for, but officials said they believe they have the gun with which the teen was shot
Neighbors tell Action News they are concerned
"There's always police activity at this house," said neighbor Robert Hargreaves. "It's just not surprising that things continue to happen at this particular house."
This is the fourth shooting since Friday involving a teenager in Philadelphia, two of which have been deadly.
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