The crash happened just after 3:30 a.m. when a 2017 Toyota Camry lost control on I-495, careened through the median, and hit a tree, Massachusetts State Police said.
The child was taken to Lawrence General Hospital and then airlifted to a Boston hospital, police said.
The 33-year-old driver suffered minor injuries in the crash. The woman and child were from Nashua, New Hampshire.
No charges have been filed in the crash, but police said they are still investigating the cause of the incident.
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