Can an out of state beneficiary's attorney (also out of state) file a petition to have me (a Ca resident) removed as trustee of a Ca trust?

There are four siblings, including me. My three siblings have had extensive alcohol and drug issues. I left and came to Ca as a young person, went to school, and became an RN, My dad needed help when he was older and my husband and I took him in. I got him good medical care and he did well for several years. He didn't trust my siblings for several reasons including their life styles. He left specific guidelines in their trusts. They have been extremely jealous and malicious. They accuse me of directing our dad, although anyone who knew him should know he was opinionated and set in his ways. They claim he had dementia. My sister, who lives in MT, has hired a MT attorney who claims she is going to file a petition in MT to have me removed as trustee if I don't resign and provide an accounting of the trust for the last approximate 5 years by the end of this week. My sister is "claiming" she hasn't seen any bank statements among other falsehoods. It is a Ca Trust and I am living in Ca.