Question: What is the date of death of Queen Hyohyeon's husband?
Sentence (from "Queen Hyohyeon"): Queen Hyohyeon (27 April 1828 – 18 October 1843) (효현왕후 김씨) was a wife and the queen consort of King Heonjong of Joseon, the 24th monarch of the Joseon Dynasty.
Relevant evidence: Yes