Methods and apparatus are provided for active vehicle cabin occupant detection system. The method includes predicting the presence of a vehicle occupant during operation of a vehicle in response to a door sensor indicative of a door opening, a carbon dioxide level and a pressure sensor in a passenger seat indicative of the vehicle occupant in the passenger seat, detecting the presence of the vehicle occupant using a vehicle cabin motion detector in response to the vehicle being shutdown, confirming the presence of the vehicle occupant using an infrared camera to detect a thermal signature of the vehicle occupant in response to the predicted presence of the vehicle occupant, and transmitting an alert via a wireless transmitter indicative of the presence of the vehicle occupant.