Lynn police say the baby was taken to a hospital but did not appear to be seriously hurt.
The woman was struck Sunday after two teens asked her for directions so they could call for a ride. Eighteen-year-old Moises Baez and 17-year-old Amanda Arsenault tell The Daily Item they watched the van run over the woman several times and helped pull the baby to safety. Baez says he yelled at the driver to stop.
The Essex district attorney's office identified the woman as Kathleen Partland, the baby's grandmother.
The driver is from Revere, but his name was not released pending the investigation.