Harriet Watson, mostly referred to as Harry, is an unseen character featured in BBC's Sherlock. She is John's unseen older sister and the aunt of Rosamund "Rose" Watson. She is an attempted recovering drug addict, but can't seem to stop.


Harriet is the older sister of John Watson and goes by the nickname, "Harry." Entering a relationship with a woman named Clara, Harry and Clara marry. Harriet constantly worries about her younger brother, but John refuses her help. She and her wife later get into several fights, causing Harriet and Clara to separate and both go through a divorce. Harriet later gives John her cell phone in order to forget her wife. {[SmallEp|A Study in Pink}}

At an unknown point, Harry and Clara's divorce goes through and Harriet seemingly goes off the drinking and reconcile with her brother. John later plans to visit Harry during Christmas. ("A Scandal in Belgravia")

Mary inquires if Harry will be coming to the wedding reception; however, even though he invited his older sister, John doubts she will attend and says that a bar and his sister do not mix well. ("The Sign of Three")

She later becomes an aunt to Rosamund Watson, but does not attend her niece's baptism. ("The Six Thatchers")


  • Harriet often swears, leaving John having to delete several of her posts.