I came home to find a Notice of Termination of Tenancy on my door this evening giving me 60 days to vacate the house my husband and I have lived in for 4 years. The house is owned by his mother who is no longer able to handle her own affairs leaving his older sister to act as "Attorney in Fact" on her behalf. My husband has been incarcerated for 3 months now and there is a good chance he may be gone for quite a while. We have lived in this house rent-free for 4 years now but according to another family member, they do not want me residing in the house while he is in jail for whatever reason. There has never been a rental agreement or lease; the agreement was verbal between my husband and his mother. I was also informed by the other sister that my husband can have the house back as soon as he is released from jail, but I cannot live there without him even if I am his wife. Do I have any legal recourse or am I just plain screwed?

If the sister has a valid power of attorney, then she is legally empowered to transact business on behalf of her mother. So, yes, she can evict you. Without a written lease specifying otherwise, she has to give you the statutory amount of notice specified by your local ordinances. It's 60 days in many places in California, but it could be more in others.