My dad refuses to leave the house & doesn't want anyone to come to the house. I also have an Alcoholic brother who says he will take him and is not trustworthy. Currently, I am taking them to medical appts., making decisions my Mom needs help with, watching her lose her memory and deny it and calling doctors, etc. My brother has taken a loan out on my parents' house, he lives large and is in debt (lives in Beverly Hills)-I am Executor of their Trust and feel powerless in the face of my mother's stubborness.
If your brother has obtained a loan against your parents house, either (a) your parents are the borrowers (i.e., signed for the loan), and allow him access to the funds through drawdowns which they make, or (b) your brother is a co-owner of the house.
If he's spending frivolously, and if the loan is a HELOC, it's time for either or both of your parents to put a stop to this and remove his authority to access funds. This would depend again on whether they're providing funds to him through the loan or whether he's named as co-owner on the deed for the house.
An Executor would handle matters under a Will; a Trustee handles them under a Trust. Are you sole Trustee? Or are your parents or one of them Trustee with you as co-Trustee or Successor Trustee? You might have authority to act now, depending on how the Trustee(s) is titled.
Has the Trust been funded? This means that assets governed by the Trust are retitled in the name of the Trust. I raise this question specifically b/c of the house and the loan which your brother is accessing, as well as to determine whether or not assets still might need to be retitled in the name of the Trust.
You don't mention if you're proxy under any POA. Could you clarify that please? It could make a difference in what action you could take to reign in your brother's spending.