Estate Law Questions? Ask an Estate Lawyer.
Hi and welcome to JA. I am Ray and will be the expert helping you tonight.
Here the brother can challenge the will and trust based on undue influence and lack of capacity.The father was vulnerable as you state and certainly unduly influenced in this situation.
The brother will need to file a civil suit where probate and the trust are located and challenge to set both aside.If he prevails the laws of intestacy would apply and the proceeds split equally here.
I appreciate the chance to help you tonight.Please let me know if you have more follow up.Thanks again.
Probate lawyers here by city with ratings for your brother.