A child car seat with a built-in cushion switch that closes when the seat is occupied. Also, push type switches are added to at least one of the vehicle's side passenger doors with signals being routed to a micro-controller unit, which determines when the car seat is occupied AND when one of the doors is open and enables the vehicle's internal beeper alarm, thereby reminding any occupants exiting the vehicle that a child is strapped in the back seat. Additionally, an inside temperature sensor is coupled to the micro-controller unit, which sets off a loud external alarm such as the vehicle's security alarm, when the temperature inside the vehicle goes above or below a safe preprogrammed environmental range. This is an additional safety feature that will get the attention of people outside the vehicle, indicating that a child is trapped in a dangerous environment inside the vehicle and needs help.