Name and birth date from Simpson Family Tree, Jan Smith.

Ontario Marriages
William Simpson to Catharine Graham, July 27, 1848 by license. [ I can’ decipher the location. It definitely not Mosa, but is something like Alpin]. Middlesex, Ontario

In the 1851 census Mosa, Middlesex County, Canada West. William Simpson, farmer, born England, Free Church, age 36. Cathrin [as spelled] Simpson, born Ireland, age 27. Agnus [as spelled] Simpson, born Canada, age 3. Thomas Simpson, born Canada, age 2.

In the 1861 Canadian census Middlesex, Canada West.
William Simpson, farmer, born England, E. Methodist, age 43.
Catherine Simpson, born Ireland, age 36.
Agnes Simpson, born Upper Canada, age 12, member of family, attended school within year.
Thomas Simpson, labourer, born Upper Canada, age 11, attended school, member of the family.
Robert Simpson, born Upper Canada, age 9, attended school.
Mary M. Simpson, born Upper Canada, age 7, attended school, member of the family.
Jane Simpson, born Upper Canada, age 5, member of family.
Isaac J. Simpson, born Upper Canada, age 2, member of family.
Elizabeth A. Simpson, born Upper Canada, age 1, member of family.
[The next family is that of William’s brother George.]

In the 1871 census Mosa, Middlesex West. Head William Simpson, age 56, English, farmer. [This is already transcribed and Individuals are listed separately]

In the 1881 census Mosa, Middlesex West, Ontario. William Simpson, age 65, born England, Methodist Episcopal, farmer. Catharine Simpson, age 55, born Ireland. Thomas Simpson, age 30 born Ontario, farmer. Mary Simpson, age 27, born Ontario. Jane Simpson, age 24, born Ontario. Isaac Simpson, age 22, born Ontario, farmer. Elizabeth Simpson, age 20, born Ontario. Elorn [Probably Helen] Simpson, age 18, born Ontario. Catherine Simpson, age 16, born Ontario. William Simpson, age 14, born Ontario.

In the 1891 Canadian census Mosa Township, Middlesex County, Ontario. Head William Simpson, age 75, born England, both parents are born in England, Methodist, farmer. Wife Catherine G. Simpson, age 65, born Ireland, parents both born in Ireland. Daughter Mary M. Simpson, age 35, born Ontario. Son Isaac J. Simpson, age 32, born Ontario. Daughter Cassie Simpson, age 26, born Ontario. Son William J. Simpson, age 23, born Ontario.

In the 1901 Canadian census Mosa Township, Middlesex County, Ontario. Head William Simpson, born March 10, 1815, age 86, born England, immigrated 1841, Canadian, Methodist, farmer R. [retired?], living on own means. Wife Catherine Simpson, born July 15, 1825, age 75, born Ireland, immigrated 1844, Canadian, Methodist. Daughter Cassie I. M. Simpson, born September 6, 1864, age 36, born Ontario, Canadian, Methodist. Before this entry is his son Isaac and family. After this entry is John Simpson born 1840 and his family. I’m not sure what relationship exists, if any.

Name, birth, marriage and death information from Micheline Champagne.