A system detects the presence of an unattended child within a vehicle and when the child is so detected, disables the vehicle's door locks by preventing doors from being locked or remaining locked and sounds an alarm. The presence of a child is detected by measuring pressure on the back seat and measurements above a threshold limit signify a child is present or if any of the rear seat belts are buckled a child is detected. The system can be shut off by the driver, although the system has an override in the shutoff mode so that if the temperature rises above or falls below a certain level and the presence of a child is detected, the alarm is sounded. In this mode, the presence of the child can also be detected by a motion sensor.