How do I initiate a conservatorship?

Wealthy mother has been acting increasingly irrational for at least a year. Recently she was charged with assault with a deadly weapon. He doctor and attorney have commented on her erratic behavior and difficulty working with her. Her cosiun recently, after the assault charge, came from Florida to talk and try to figure things out. Quoting from the text her cousin sent me "I think she should be confined to a nursing home. She threw a glass [of] wine, spoons, forks, and table knives at me last night at Tra de Noi restaurant. She's a danger to society, as well as to herself. Sheriff's deputy came, but I (mother's cousin) did not press charges. Otherwise she'll probably still be in jail". This is only the most recent and disturbing incident.