Thanks for your question.
Firstly, I am very sorry that you have found yourself in the difficult situation. You have obviously been very poorly served by your previous solicitor.
Your mother cannot pass on the power of attorney to another I'm afraid.
If your father does not have the requisite mental capacity to grant a power of attorney to you, in that he no longer understands the implications of the decisions put to him then you will be looking at making an application to the Court of Protection to be appointed deputy for your father.
If satisfied then the Court could effectively grant you the same powers as your mother had in respect of his affairs under the LPA/EPA she held. In order to get appointed as quickly as possible I would suggest that you ask a local solicitor to prepare and submit the application for you.
You can find Uk solicitors through the following Law Society Website search engine:-
Enter either "wills and probate" or "trusts law" in the area of law box, they will have solicitors in those departments who can do this for you.
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