The pair were crossing Valley Road at Birchwood Terrace around 7 p.m. when they were struck by a four-door Chevy Impala, authorities said.
The elementary school-age boy was taken to the emergency room at St. Joseph's Regional Medical Center in Paterson in serious condition.
The woman was pronounced dead at the hospital at 7:46 a.m.
The driver remained and his passenger remained at the scene -- barely a mile down Valley Road from where a 78-year-old Wayne woman was struck and killed Monday afternoon.
The Passaic County Prosecutor's Office and Wayne police were investigating the incidents, which one responder said were both "tragic accidents."
They asked that anyone with additional information about either crash to contact the prosecutor's tips line at 1-877-370-PCPO or email@example.com or contact the Wayne Police Department Traffic Division at (973) 694-0600.
ALSO SEE: A multi-agency chase that began when a driver involved in a domestic dispute purposely tried to run over a Wayne police officer at the Willowbrook Mall ended with his arrest Tuesday night, authorities said.
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