Meet the Tracki (2020): a mini GPS tracker that lets you monitor the location of your car, kids, pets, and everything in between. It is compatible with iOS, Android, Alexa, and web connected devices. Its SIM works worldwide.
You can send a beep to the tracker. It runs on a battery that lasts for 30 days. The Tracki measures 1.8″ by 0.55″ by 1.5″. You can find out more about it here.