A Honda Accord and an SUV collided at the intersection of Remsen Avenue and Seaview Avenue in Canarsie just before 9 p.m.
The Accord lost control and jumped a curb, hitting the pedestrians and pinning them against a fence.
The woman, 32, died at Brookdale Hospital. Her 6-year-old son remains in critical but stable condition.
Both drivers remained at the scene.
Neighbors say there is so much speeding on the two streets, they have tried to get help from the city.
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