Power of Attorney

Does a general power of attorney in Texas act as a durable power of attorney?
My mother has a general power of attorney in Texas that states ' This general power of attorney shall not terminate on disability of the principal.' Is this general power of attorney thus operating as would a durable power of attorney?
What options do we have regarding my brother's care and power of attorney?
My sister in law has cancer and wont be around much longer, she has 2 kids from a previous marriage and is married to my brother who had a major brain injury 4 years ago and is disabled. We suspect she has signed over power of attorney for my brother to her son (brothers step son) We suspect she had him sign a document which allowed this but no one in our family was made aware. We have been told there is a $100,000 dollar life insurance policy which would go to my brothers step son, and he would manage my brothers finances. Our fear is we wont have any say in my brothers care and my brother isn't able to take care of himself. What options do we have? Also we live in MN and they are thinking about moving to IA which where the step son lives.
How does my mother's incompetency affect her other children's rights?
My MOM is 88 yrs old and while at a skilled nursing facility for rehab for a broken shoulder. She was deemed incompetent and I signed a document that allows me her daughter to make health decisions on her behalf. We live in the state of Florida. How does this effect her other children if they are all talk and no action, meaning they want a say but are not willing to put in the time and effort.
Do I need a durable Power of Attorney for my mother in Texas?
My mother lives in New Mexico and own real estate in Texas. She is 84 years old and wants me to take over selling her house in Texas and I live in Dallas, TX. Will a durable Power of Attorney be the form I need? She wants me to have business and medical Power of Attorney to conduct her affairs. Since she is a resident of New Mexico will a form from the state of New Mexico handle business and medical decisions in Texas? Please advise the correct POA and do I need to only get the form in New Mexico or do I need to get forms for Texas and New Mexico? Thanks?
Does a notarized durable power of attorney in Texas need witnesses?
Does a general durable power of attorney form (no medical decisions) in Texas need to have witnesses if the form is notarized properly?