What rights does the unmarried partner have when one of the couple passes away?

She has no legal interest in the home or possessions through intestate succession. She is entitled to the personal property she can prove is her own.

If she was not on title, she has no right to stay in the house. I do not think California has updated the probate laws to include domestic partners. That is why it makes little sense for a woman to live with a man without getting married. There are some cases in which a widow got back some money because she could prove what amount of her own funds she put into the home [repairs, mortgages, etc.]. She could retain the items she bought herself and did not give to him as a gift, but that is going to be hard to prove. She needs to communicate immediately with his family to establish what her contributions to the relationship were. ?It may not be worth while to hire an attorney to recover her items.