The safety and health of children are essential issues not only for households but also for society. Missing Child is a severe strike to a family. It causes severe trauma memory and affects family members both psychologically and physically. Incidents like this also spread a feeling of fear among the local community. Many efforts have been made to help with this problem, such as the Amber Alert system, the location-tracking functions in the operating system in smartphones. There are also many safety apps in the app stores trying to prevent this kind of incident. However, there are still things that these apps do not cover: What should the parents do when they lose contact with their children and feel worried? This project explored ways to provide guidance for parents and tried to find a way to balance the privacy-safety tradeoff
