William Foley (1809 - 25 august 1841) was the maternal grandfather of Arthur Conan Doyle.
In his auto-biography Memories and Adventures (1923), Arthur Conan Doyle wrote : « [William Foley] was a young doctor of Trinity College who died young and left his family in comparative poverty. »
- 1809 : Birth.
- 1835 : 24 april, marriage with Catherine Pack at St. Andrew church, Dublin.
- 1836 : 14 february, birth of his son Thomas Scott Foley.
- 1837 : 8 june, birth of his first daughter Mary Josephine Elizabeth Foley, the future mother of Arthur Conan Doyle.
- 1839 : 19 april, birth of his second daughter Catherine Mary Agnes Mullin Foley.
- 1841 : 25 august, he died at 32.