My Mom made my "devious" brother both her financial POA and the executor of her estate. What do I do?

She has several real estate assets, as well as 4500 a month being direct deposited into her checking account, which of course has my brother's name on it also. For many reasons it is clear to me that he is using her funds for his own benefit, while she has many debts that will need to be paid at her passing, He is being very secretive about the whole thing, won't tell me much, and I feel at a total loss because there is no one who can be 'the watchdog' in all this. Is there anything I can do besides find a lawyer who will represent me pro bono? (I'm on disability). Here's an example of what I'm talking about: he only works half the year (seasonal job) so how is he supporting himself now that the job has ended? He's about to take his SECOND week long california vacation in less than six months! He could never afford that with his own income! What can I do? Mom is in a nursing home in my state, not the state that my brother lives in, which is also where the revocable trust was made. I've been told I need a lawyer, but I can't afford one. What do I do? Mom is on her last legs at the end stage of Alz. and probably won't be around much longer.