The contact rented a 2024 Hyundai Palisade. The contact stated that while the vehicle was in park(P), she exited the vehicle and proceeded to the rear of the vehicle. The contact stated that while attempting to open the rear latch, the vehicle started rolling backward. During the incident, an occupant who is the contact's daughter jumped out of the vehicle to assist the contact with attempting to stop the vehicle. A 4-month-old child was in the vehicle during the failure. The vehicle collided with a vehicle and was scratched and then collided with the mirror on another vehicle where it came to a stop. The contact sustained knee and leg inquires. The contact was pending a doctor's appointment. A police report was filed. The manufacturer was notified of the failure. The failure mileage was unknown.