Hello. The short answer is "yes", your mother may appoint you as both the agent under her power of attorney documents (medical and durable POA), and as executor under her Last Will and Testament. There is also no problem with you being a beneficiary of her estate and acting as the executor of her estate. I wish you and your mother the best of luck.
I agree with Attorney Dietlein. This can certainly be done, and it is pretty common, particularly in cases like yours, where it is a relatively small family. You obviously want to get with an estate planning attorney in Texas as soon as possible to determine what your best options are. The creditor issue will help determine how best to proceed. It almost goes without saying, but you definitely want to retain an attorney to help you with this. Estate planning in general should be handled by a professional. When you add some of the complicating factors mentioned in your summary, this becomes even more a no-brainer. Rather than waiting for someone to provide an answer on Avvo, I would schedule an appointment with an estate planning attorney, right away. If you do not have an idea who to call, click the "find a lawyer" link below and type in "estate planning" attorney in your area. This should give you a decent list of people to start with.
Best of luck to you and your mom!
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The quick answer is yes. It depends on when and what he did with POA. POA expire at death so if he transfered property with it, he could disquaify himself as executor. If he used POA adversely to other heirs there mabye an issue.
Probably yes. Without going over all the facts, I can't say for sure. What you have described can be done without any adverse consequences and is actually done very often. However, there are some issues that can arise in any estate planning case. I would suggest contact an estate lawyer in your area