An AirMed One medical chopper flew the boy to Hackensack University Medical Center with head trauma after the crash near Exit 66 (Mahwah) just before 3 p.m.
A sedan driven by Christine Ryan, 27, of Bartonsville, struck a Lincoln Navigator that was slowing for holiday traffic, sending it into a guardrail and ejecting the boy out the back window, witnesses told responding officers.
An earlier Daily Voice report that Ryan was carrying drugs was confirmed.
She also was charged with DWI and assault by auto, among other offenses, State Police said.
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