| Rosamund Mary Watson |
|Parents|| John Watson |
Mary Morstan (deceased)
|Family|| Harriet Watson (paternal aunt)|
Molly Hooper (godmother)
Sherlock Holmes (godfather)
Martha Louise Hudson (godmother)
|Behind the scenes|
Rosamund is conceived prior to the marriage of her parents John and Mary Watson. During the wedding their friend and Rosie's godfather Sherlock Holmes deduces that Mary is pregnant, and tells them the news during the reception.
Rosamund is named after her mother, having her mother's first and middle name, however her mother's true last name is unknown.
- It is revealed that Mary chose the name after her own original identity, Rosamund Mary. Her father had originally liked the name "Catherine",
- "His Last Vow" (mentioned) (Mary's pregnancy)
- "The Abominable Bride" (Mary's bump)