My folks have two joint accounts, checking and savings. Both accounts are in their trust, they are the trustees. I am the successor trustee. It's getting to the point where I should be a signer on the checking account. Mom agrees, Dad has dementia and will not. I don't have DPOA for either one yet, again Mom will be willing, but not Dad. Is a DPOA useless because the accounts are in their trust, or if I have it for Mom can I write checks? I'm confused.