Question: When was Hester Maria Elphinstone, Viscountess Keith's mother born?
Sentence (from "Hester Maria Elphinstone, Viscountess Keith"): Hester Maria Elphinstone, Viscountess Keith, born Hester Maria Thrale (17 September 1764 – 31 March 1857), was a British literary correspondent and intellectual.
Relevant evidence: No