Hi clgph02
welcome to TP - there are lots of people here with wide experience - do have a good mooch around as there's lots of info in the threads
someone constantly making phone calls is a regular concern - your situation is a bit trickier as your mum is calling her son's care home, which is understandable but not viable if she does it so often
does she dial the number or is it saved on the keypad - you could delete it, but then she can't call at all, which will worry her
is it possible to arrange with the care home that they call her once a day and agree a certain time which is convenient to both of them - then put up a notice by her phone to remind her when the call will be - will only work if her understanding is strong enough and her anxiety will not override this, so she will call anyway
is it possible for the home to not answer except at an agreed time - probably not something they'd agree to, and not getting an answer may make your mum more frantic
an extreme idea - could you buy a cheap mobile, record an answerphone message that says something like the care home is busy but will take a message or call her back - then leave the mobile turned off so all calls go to answerphone - tell your mum the number has changed and have her call the mobile number instead of the care home - BUT the care home really call her once a day so that she does get a chance to speak to a member of staff and/or her son - again, lots of potential problems with this!
as for her calling you - could you let her go to answerphone, and only call back when you want/need to?
sorry - not very useful suggestions