Police say the 63-year-old sister was shot during an argument in the basement of the family's home. She was shot in the chest and was pronounced dead at Kings County Hospital.
A younger relative in her 30s, was grazed to the head. She is in stable condition in the hospital.
The gunman was taken into custody. His weapon was recovered.
The dispute may have stemmed from the living arrangements in the house. Perhaps they were trying to kick the gunman out, police officials said.
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