Question: What is the date of death of Lynda Bird Johnson Robb's mother?
Sentence (from "Lady Bird Johnson"): "Lady Bird" Johnson ("née" Taylor; December 22, 1912 – July 11, 2007) was an American socialite and the First Lady of the United States (1963–1969) as the wife of the 36th President of the United States, Lyndon B. Johnson.
Relevant evidence: Yes