Who's paying for your kids cell phone?

OK so most of us pay for our kids cell phones.  I did make them pay for their data plans but the phone is still on my family plan.  It is the only bill I pay for my girls, both of which live away from home.  I think that this should mean that they should answer the phone whenever I call?  Sounds like I am a bit of a dictator but I just get so ticked when they don't answer the phone when I call.  I may call California Coll once or twice a week.  I call Jul more, but only when it is something I think they want to hear.....WHATERVER.. I take comfort in knowing that the day will come when they have kids and then they will see!  hahahahahah