Melissa Castillo DeLoatch, 32, later died at the hospital. Family members say she threw herself in front of a stroller, and it was revealed Thursday that she was pregnant with her seventh child.
Police believe an argument between the family and the driver, identified as 35-year-old Jason Mendez, of Washingtonville, may have precipitated the 2 p.m. attack in the parking lot along Central Highway in Haverstraw.
A 7-Eleven employee told Eyewitness News that Mendez was smoking outside the store and became enraged when the father had asked him not to smoke around the kids.
An argument ensued, which the worker says came to an end when Mendez got into his car and plowed into the 7-Eleven, striking all eight family members.
Police say he then reversed the vehicle and drove forward again, striking the victims a second time.
"She was laying on the ground," witness Allison Rodriguez said. "Carriage was there. Nobody was around her. We just kind of knew she wasn't going to make it."
The father was also seriously injured, as were three children ages 3, 2 and 11 months. Two of the children remain in the pediatric ICU.
The older three children, ages 10, 7 and 5, all from a previous relationship, were also hospitalized, but none of the injuries are considered life-threatening.
Relatives say the 10-year-old is hearing impaired and that one of her cochlear implants was dislodged in the collision. Investigators weren't able to find it.
Police said that when they arrived on the scene, the suspect was still inside his car and was armed with a knife.
"He didn't say anything initially to the police officers," Haverstraw Police Captain Martin Lund said. "He refused to drop the knife. Then he was tased at the scene and taken down."
Mendez is charged with second-degree murder, seven counts of second-degree attempted murder, menacing, criminal possession of a weapon and resisting arrest.
He has pleaded not guilty.