The incident happened just before noon along Route 57 (Feeding Hills Road) in Southwick, MA, Hamden County District Attorney Anthony Gulluni said.
The driver, a 23-year-old woman from Winstead, CT, was rushed to an area hospital with serious injuries. Gulluni said the child was the woman's niece.
A portion of Route 57 near Foster Road was shut down Friday afternoon as police cleared the scene. The investigation is ongoing.
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