Police say the baby, who was just 28 days old, died after the crash around 3:30 p.m. on Klockner and Whatley roads.
Police say a Hyundai Elantra was travelling westbound on Klockner Road approaching a traffic light at Whatley Road. At that time, a GMC Sierra truck was travelling eastbound on Klockner approaching Whatley.
Police say the Elantra, while making a left turn, failed to observe the GMC Sierra approaching.
The Sierra driver attempted to avoid an impact by steering left.
The front right portion of the GMC then struck the passenger side of the turning Hyundai.
The 30-year-old Elantra driver and her two children, a 5-year-old girl and 28-day-old boy, were transported to Robert Wood Johnson University Hospital Hamilton. The baby was pronounced dead a short time later.
A 50-year-old passenger in the Elantra was transported to Capital Health Regional Medical Center for treatment of her injuries.
The investigation continues.
Any witnesses to the crash are encouraged to contact the Hamilton Police Traffic Unit at (609) 581-4024.