As far as rules go, the license holder is responsible for how the radios are used. Lets say the family in NY program a part 90 radio to receive the local FD, however due to an error they transmit on the FD channel and give your callsign, you could be on the hook. Now this is a bit exaggerated but has happened from time to time. Another example is the family in NY using a radio that is not certified by the FCC and causes interference on another channel. Or, because they are in NY, using channels 19 and 21 north of line A (I think those were the channels) which is also an easy violation for someone to make if they haven't read or understood the rules. How I manage everything is, I program the radios under my callsign myself. By doing that I can assume all responsibility should something go wrong. My family knows and understands the rules of GMRS, and everyone has a 3 digit ID code, (First digit identifies the location and last 2 are unit numbers) So if a complaint comes in about WRAK968-103, I know its my brother, 202 is my step mother and so on. Some people use one digit ID, (WRAK968-1). The three digit system may work for you so that should there be a problem you will know where the problem is, and possibly who the problem was caused by.