In the 1900 US Census for District 107, Dayton, Tuscola County, Michigan the family of John Locke was enumerated as follows:
Dwelling #120; Family #121
Locke, John; Head; W; M; b. Oct 1855; 44; Married 10 years; b. Michigan; Father b. Vermont; Mother b. New York; Farmer; Employed full year; Can read, write and speak English; Rents farm home; Farm Schedule 94
Locke, Minnie; Wife; W; F; b. Apr 1848; 52; Married 10 years; Mother of no children; b. New York; Father b. England; Mother b. New York; Can read, write and speak English
Locke, Clarence M.; Son; W; M; b. July 1883; 16; Single; b. Michigan; Father b. Michigan; Mother b. Canada-English; Farm laborer; Employed full year; Can read, write and speak English
Locke, William W.; Brother; W; M; b. Feb 1853; 47; Widowed; b. Michigan; Father b. Vermont; Mother b. Michigan; Farm laborer; Employed full year; Can read, write and speak English
Locke, Amanda; Mother; W; F; Sep 1826; 73; Widowed; Mother of 5 children; 4 children living; b. New York; Father b. Vermont; Mother b. New Hampshire; Can read, write and speak English