A lightweight wearable sensor that attaches to a dog’s or cat’s collar with a companion mobile app and AI-driven analytics to continuously monitor key health indicators such as activity, rest, respiratory rate, heart rate, itch behaviors, and—on dogs—water intake. After a baseline period, the system compares ongoing data to individual norms and flags deviations that may signal emerging health issues, providing early alerts to pet parents for timely follow-up and veterinary evaluation.