My mother told me at age 63 that I was adopted as a little baby. In spite of her "infertility" she had a male child 8 years later than myself. He is 56 now and has never worked. He cane back from overseas six years ago and installed himself as carer. Neither parent then needed one. Last year he persuaded her to change Will and make him POA. I am all alone and in poverty. I am now completely disinherited as he told me they owe me nothing as I was adopted. Enabling father lets it happen.Very wealthy family but looking back now I can see I was always controlled and abused by Narc. Mum. I feel betrayed and used as I loved them and they were all I knew.
If you were legally adopted by your parents and they kept that secret until you were 63, then they loved and cared for you at some point in your life and probably still do.
I would not take your brother's or your parents' word for it that they've changed the will. Not unless you've actually seen it. So call your brother's bluff. Your parents making your brother who lives with them POA, does not mean they disinherited you from their will. Make them show it to you. If your brother is bluffing and they didn't actually change their will, then you need to have a talk with them and keep a close eye on their situation to make sure your brother doesn't actually have a new will drawn up.
Always remember to never think of their money as yours. Elderly people are hard enough as it is to deal with, but add wealth and they become absolutely intolerable. I know it's hard for you because you're poor, but you might have to suck it up a little bit with your family. In the long run it will be for your own benefit.
Finally, try to resist interpreting your situation through the filter of being adopted...there are plenty of people on this forum who have the exact same issue as you, only they are biological children. Being adopted may have absolutely nothing to do with your situation. I don't deny it is causing you much pain and sorrow. I wish you peace in your heart as you move beyond your family's dysfunction.
I live in Arizona and you can not disinherit an adopted child, it is illegal. I would check with your state and then let it go. If it is illegal what a great surprise your brother is in for when your mom dies. Imagine the surprise that he doesn't get it all.
I am truly sorry that you are being discarded by a person that chose you and made you her daughter. No one deserves what you are going through but, you know and you are in control of your future. Make it wonderful, that is the best way to have victory in this crummy situation.
Why I ask is that my cousin's Mom also told her [she was in her 50's] she was adopted because after having 4 sons she wanted a daughter so they adopted. My cousin knew it wasn't true and that it was the "dementia talking".