A system includes video cameras arranged to monitor a vulnerable person, and a processor system that receives video frames from the video cameras, the processor system comprising a processor and a non-transitory, computer-readable storage medium having machine instructions executed by the processor. The processor detects and identifies objects in a current received video frame, classifies an identified object as the person by applying a facial recognition algorithm that identifies the person, determines a posture of the person by identifying joints, limbs, and body parts, and their respective orientations to each other and to a plane, and immediately discards the current video frame. The processor then determines a change in motion, of the person, between the current received video frame and one or more prior received video frames, and, based on the determined posture and the change in motion, determines that the person has experienced a defined event.