Family falling out present and future

Citizens Advice may be able to assist you or they will tell you to get proper legal advice.

It all depends on the wording of the will a solicitor will interpret it for you. For a will to be overturned there has to be something grossly unreasonable. An example of this would be cutting out the whole family who had been promised a legacy and leaving the lot to the donkey sanctuary.

You say MIL retained a 1/3 share of the house herself depending on the status of that share it may be part of her estate or passes straight to you. Her will (if any) will say how that should be divided, if her son is omitted he has no grounds to contest the will.
If on the other hand if her “estate” includes a share of the house the value has to be distributed according to the will. The letter you mention explains why she made the decision and would not form part of the will or override it.

You need to take the deeds to the house and the will to determine the true status of everything. Also do remember if she has to go into care, her share of the house, along with any other assets will need to pay for her care home fees

I would agree, speak to a solicitor. They can advise you best.

Speak to a solicitor and confirm that everything is above board, but if your MiL has properly drawn up will, accompanied by a letter explaining why she has made the decision that she has made and it is clear that your MiL was in her right mind at the time te will was made, then there is nothing your BiL can do about it.

But as I said, for your peace of mind, get everything reviewed by a solicitor specialising in wills and probate.

So sorry to read this.
As someone else has suggested, perhaps speaking to a solicitor (probate specialist) and ensuring that things are 'watertight' will ease your concerns?
I'd also suggest printing off emails and keeping a record of any contact from him.....
Best of luck going forward.

If it comes to it you could take equity release and pay the brother off that way. Although anyone should be able to leave what they want in their will to whoever they choose. What grounds would he contest the will on, when his mum lives with you and between you and your husband provide her care and have done for over 10 years. I think you're worrying unnecessarily.

My sympathies to you for having to deal with this difficult situation. I didn't want to read and run, but I really can't advise other than to suggest that you seek proper legal advice to try to preempt any move by your BiL.