what personal choice rights does an adult have, who suffered some memory loss due to brain injury/coma, and lives with parents?

The answer would depend on whether the parents have guardianship over the adult and what is the mental condition of the adult. Since the facts are not specific, I cannot give you any other advise than to contact a local attorney.

You do not indicate whether or not the mother has legal guardianship of this person. His rights would depend on whether she has a legal right to make decisions for him or not.

Who is the legal guardian? You can contact a lawyer in CA to advise you on your rights.

You might find my Legal Guide helpful "How to Choose A Lawyer For You"

http://www.avvo.com/legal-guides/ugc/how-to-choose-a-lawyer-for-you

You might find my Legal Guide helpful " What Do I Tell My Lawyer"

http://www.avvo.com/legal-guides/ugc/what-do-i-tell-my-lawyer

Good luck to you.

God bless. I am in Chicago and do not practice in your state.

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