What if one dementia effected parent forces the other to redo their will & my sole sibling knew & helped take all money away from the other?

My sibling assisted my father to close all my mother's accounts and put all money in savings with his and fathers name only. Mother was tricked to selling home she purchased next to me so I could take care & watch for anything she needed. But after a 4 month illness with mental capacities temporarily challenged both father & brother sold home took all moms money & won't give it back to her. Mom went to work 30 years ago to keep her money away from my father who does not truly take care of her. Now I'm trying to take charge of medications (He was stealing) & am getting accused of stealing his money while I don't "really" take my mom to "real" doctors & instead just act like a doctor. This is delusional as I keep doctors receipts and cannot possibly prescribe medications she needs. Brother & father will not return mother's money so even her medical expenses can be paid for. Brother thinks he's rational because if mom goes in a nursing home HE claims the state will come after him but not me because I'm unemployed even though we both own homes.

My Mom now knows they "coached" her to redo the will & power of attorney papers only 6 months ago while she suffered dementia. My brother did not tell me about this (My Mom just recalled it) & now after just learning my father & brother have taken every dollar she saved, she's asking me to get it back. My brother is the sole recipient now, where before all was 50/50. My father gets violent and threatening when I ask for anything of money to take care of her (& he's continually lied to my mom saying she can have her monet anytime when in truth all has been taken & put in an unknown savings with his and my father's name only.

How &/or where do I even start to fix this mess. I don't have the financial means to take my mom in with me but I do help clean, shovel snow and see my mom once or twice a day (both parents live in their own home). She is afraid of asking for her money back when she's home with only him. My father takes her retirement and social security checks every month & puts them in the "secret" account he and my brother only own. The new will also gives all my mom's possessions to my father or in case of his death, my brother. Old will left nothing to my father. Now she's asking me to help change will back to 50/50 when she currently has nothing. Also wishes to make me power of attorney when old will said it should be my brother. New will (& legal documents) name my father as power of attorney then my brother in his absence. This is a mess & I don't know where to begin. Any insights/suggestions would be appreciated as this is beginning to affect my health! I don't have the ambition to keep driving to their home every time something is needed & then being threatened by my father. My Mother & father call me in excess of 20 times a day. My father isn't helpful to mom with any daily tasks-he takes care of himself only.