My father passed away three years ago with no will or living trust. He didn't have any stocks or monies left except for a house that he and my mom owned. A year after he died, she transferred the ownership of the house only to her name without telling my sister and me. She is now living with her boyfriend in the same house. Now, my question is, do I have any rights or share with the ownership of this house? With her changing the ownership only to her name, was it legal for her to do that? Thank you and hoping to get an answer to these questions.

Los Angeles, CA