It depends on whether just you and your brother have moved, or your mother as well. If just you and your brother have moved, there’s no need to update the power of attorney. It’s still valid. The use of your address and that of your brother’s on the document are for identification only and have no legal significance. If your mother has also moved, it’s probably a good idea to update the power of attorney. If she’s still in the same state, the existing document is still valid, but it’s more likely that banks and other institutions will accept it if it has your mother’s current address. More importantly, if your mother has moved to a new state, it can be important that she execute a new durable power of attorney applicable in that state. While all powers of attorney should be accepted nationwide, as a practical matter local institutions more readily accept local documents.
For more information about powers of attorney, click here.