Thank you for your question
My name is Clare
I shall do my best to help you but I need some further information first
Why do they object to you having these Powers given that you have her care?
Are you aware that the site charges extra for a phone call?
Please do not worry - there is nothing that your sister's can do no matter what they threaten.
Whilst I understand that you do not wish to cause your mother any distress it is your home and you can decide who does or does not visit and when.
If you have a friend who is willing to supervise then it cold be best to arrange visits when you are not there - but certainly not to allow then to take her out (unless this is what you want)
You have complete control over everything - and the fact that you are clearly in touch with Social Services means that there is little your sisters can actually do
Please ask if you need further details
That would be an excellent idea - protect the carers by giving them written authority to exclude anyone other than the named visitor!