Family is abusing mother financially by stealing from her bank accounts. What can we do?

Is your mother in a position to be aware of the stealing? Does she condone or make excuses for it? Is the adult child on the account that they’re taking money from? The first thing to do is cut off access to any more money. If the person doing the stealing is on her accounts, they need to be removed. If mom is aware of what’s going on and being compliant in it, it depends on whether she has a sound mind. If she does, it’s her money to let go of as she pleases. More info would be helpful