Systems, devices and methods of using sound detectors, motion detectors and temperature sensors inside vehicles for activating alarms to protect vehicle occupants that include babies, children, infirm, elderly and pets. Headrest mounted sound detector(s), motion detector(s) and temperature sensor are used wherein detected sound from the sound detector can activate the motion temperature sensor and motion detected to activate adjacent or remote alarms. when unsafe cold and warm interior vehicle temperatures are reached. Low battery indicators such as audible alarms, chirp sounds and lights can be used to indicate low battery power supplies.