Maries, I am sorry I was a bit brusque but your last email changes the picture. If you worked unpaid or for low pay in a family business on the understanding that you would inherit half the estate on your death, if your mother makes a will leaving everything to your brother you can sue for proper provision from the will because of the circumstances around your work in the family business.
How ever taking into account your limited income. Your best tactic is to make no effort to get your mother to make a will because if she dies intestate the estate will be shared equally between the two of you. You will get your half. Perhaps the time has been reached where your brother should be left to sort his own problems and you should protect yourself. Discouraging will making protects your interest and costs nothing.
You will need a solicitor to deal with the intestacy when your mother dies and that will be paid from her estate. When this happens visit several solicitors and ask them how much they will charge, this is usually quoted in terms of a percentage of the value of the estate. A solicitor will make sure that the estate is divided equally and fairly
Can I use my bus pass on London buses?
I've got another 'keen'... Ouch!
Elderly fellow gran has become loudly racist