Just to help set expectations ... the Apple AirTags are NOT anti-theft devices. Using them in such a manner will end with unsatisfactory results. The reason is that these tags rely on Bluetooth and the Apple Find My network, which consists literally of millions of other iPhones, to work. It is actually those phones' locations that show up as AirTag location updates.
The other issue is if the thief has either an iPhone or Android phone, they will be notified that an AirTag is nearby and following them. This will alert them to try to locate the tag and disable it.
Going back to the issue stated in your post. Do either or both of your parents have iPhones? Are these AirTags associated to your Apple ID? Are you/your parents participating in the Apple Family Sharing plan?