It happened around 8:40 p.m. on Route 52 near Old Glenham Road in Fishkill.
Authorities say the 53-year-old driver was operating a 2003 GMC Yukon westbound on Route 52 in the center/turn lane of the three-lane road when he or she failed to observe a mother and her four children attempting to cross the road from the north shoulder.
The mother, 29-year-old Zuleyma Lopez, and 10-month-old Abel Torres-Lopez were pronounced dead at the scene.
"She was right in the middle of the road, and the stroller was almost on this side of the road," witness Bill Diaz said. "And the kid that was trying to get up, he was like in the middle of this lane."
The three remaining children were transported to Westchester Medical Center.
The driver stayed at the scene, and so far, no arrests have been made.
Elisa Nati knew the victim, who often visited her takeout business, the children by their mother's side. Nati placed signs outside her storefront urging drivers on Route 52 to ease up on the gas pedal.
"An extra second of looking at what's in front of you and where you are going, regardless if you live in the area or you don't live in the area, could make a huge impact on somebody's life," she said.
The cause of the accident is under investigation.
Anyone with information is requested to contact the New York State Police at 845-677-7300.
----------
* More Northern Suburbs news
* Send us a news tip
* Download the abc7NY app for breaking news alerts