She was born Claudia Taylor, but was much better known as "Lady Bird" Johnson. She was the wife of former US president Lyndon B. Johnson, who became president in 1963 after John Kennedy was assassinated.
She was particular known for her work towards environmental causes, even after suffering from a stroke in 2002 that left her with speech difficulties. She died recently, on July 11th.
You can read more about her life and death in a news story from ABC News.
For more information on presidential genealogy, you can read my article with hints and resources for doing research on the presidents of the United States.