Abstract: The vehicular child or pet alarm is an alarm system adapted for use with vehicles. The vehicular child or pet alarm is an in-vehicle sensor system that identifies when occupants, particularly children and pets, are in the vehicle. The sensor system is in communication with a key alarm and a case alarm. If sensor system detects an occupant within the vehicle and determines that either the key alarm or the case alarm are greater than a predetermined distance from the sensor system than an alarm is generated on the key alarm or the case alarm, respectively, and a text message is sent to a designated personal data device that is configured to receive text messages. The vehicular child or pet alarm comprises a sensor system, a key alarm, and a case alarm.