The shooting happened around 5:10 p.m. on the 500 block of Norris Street.
Arriving officers were directed to a second floor bedroom where they found an 8-year-old boy suffering from a gunshot wound.
Medics transported the victim to Crozer Chester Medical Center where he is being treated for a non-life-threatening injury.
A 19-year-old family member was taken into custody and will be charged with Recklessly Endangering Another Person and Receiving Stolen Property.
Police say the gun accidently went off when being handled.