Mary Morstan is the wife of which character from the Sherlock Holmes stories?

Mary Morstan is the wife of Dr. Watson. She is first introduced in "The Sign of the Four", where she and Watson tentatively become attracted to each other, but only when the case is resolved is he able to propose to her. She is described as blonde with pale skin. At the time she hires Holmes she had been making a living as a governess. Although at the end of the story the main treasure is lost, she has received six pearls from a chaplet of the Agra Treasure.

Mary Morstan is mentioned in passing in "The Adventure of the Crooked Man" and "The Boscombe Valley Mystery", but by the time of "The Adventure of the Norwood Builder" (after Holmes's return) Mary Morstan has died and Watson has returned to his former lodgings in Baker Street. Her cause of death is never mentioned.