Thank you for the question. I am sorry to hear about the matter. Just to clarify the Power of Attorney becomes null and void at the point of death. If she has been appointed executor of the estate by the Will (or otherwise) then it is up to her to distribute the estate as specified in the Will or by the laws of intestacy. If your nephew is a beneficiary of the estate, she is legally bound to issue him with any part of the estate which was bequeathed to him. However, if she fails or refuses to undertake her duties as an executor then at this point legal action could be taken. However, she is under no obligation to give him access to anything he has not received or been bequeathed as a beneficiary or appointed as an executor as this time. I appreciate that can be frustrating.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
Hopefully, I have answered your query in a way that is simple and easy to understand. If anything remains unclear, I will be more than happy to clarify it for you. In the meantime, thank you once again for using our services.
Should you require any further assistance on this matter, please do not hesitate to post a further questions for additional assistance.