I am the mother of two daughters who think they should talk to me EVERY day. I don't think this is necessary quite frankly. If you leave me a voicemail I will call you when it is convenient for me, if it's that darn important SAY SO in the voicemail.
I have Facebook, cell phone, office phone, home phone, texting and email - it's not like they can't reach me somehow. I have also always told them if you are that worried call the police, apartment manager, my boss, my best friend, whomever you feel would be the easiest to check on me.
Really, if you try to reach me and can't within a four hour period - please feel free to call another source something may genuinely be wrong.
I have a SIL and her mother had so alienated everyone in her family that her body was not discovered for five days and she lived next door to her own son. I certainly don't want that to happen to me.