Buttonjugs, the house has been sold and the OP has bought a house for her and her husband to live in because they left their tied property on retirement. I don't think anyone should sell their own property to help out a brother who had his share when his mother was alive.
OP, the only person who has done anything wrong, is your Mum. She should have. been quite clear in her Will why she was making this decision. It is not incumbent upon you to explain your mother's actions but if your brother ever actually verbalises his dissatisfaction directly to you over the Will, you can only explain what you 'think' her thoughts were.
My sister has moved further away from her mother over the years (which is her right) and over the years I have been the one to look after my Mum who has been hopeless with admin for years, long before her dementia started. We purchased a house between us and it goes into my name fully when she dies. She did once put my sister's name on another property but after receiving letters from my sister's solicitor demanding a number of assurances, Mum sold the property. My sister was livid. However, some years later my Mum gave a considerable sum of money to help by a house and felt she had therefore treated us equally in the long run. A recent conversation with my sister made me realise that my sister honestly thought I would put 50% of the house with my name on back into the estate when my Mum dies. Consequently, I have asked my Mum to put into her Will exactly why I get her half. Not only have I dealt with all the admin on it and worked on it to improve it, my Mum wants me to have it because she does appreciate that I have been the one there for her. My sister is still mildly pear shaped about it but the rest of my Mum's estate will be split equally and fairly.
However, it just goes to demonstrate how these things can upset the apple cart with families and why it is so important to be explicit with your reasoning whilst not hurting the people left behind.
Last weekend, in Rutland, the first statue in Britain of the late Elizabeth II was unveiled.
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