|Mentioned||Nightmare on Queen Street|
|Relationships|| Timpson Foster (husband)|
Rebecca Foster (daughter)
Mary Foster was a mathematician and lecturer at University College. She was a fellow of the Royal Society of Canada and also created tantalizing puzzles for the Toronto Gazette. Foster was also a talented painter, frequently seen painting in High Park.
Foster was married to Alderman Timpson Foster with whom she had a daughter, Rebecca. The family lived together at 13B Cumberland Street in Toronto. Her husband was murdered on the night of October 11, 1892.
Foster died of head injuries presumed to have been sustained when she was hit by a moving carriage on July 26, 1899 at the age of 41. Her autopsy was performed on August 1, 1899. In fact, when Foster's body was exhumed, Dr. Emily Grace determined she had been killed with a surgical wound. William Murdoch discovered that Foster has been murdered by Dr. Lyman Barclay who was fascinated by her mind. He then staged the carriage accident to cover her murder ("The Chair").