In the 1851/2 census for Lanark county, William is a farmer who was born in Canada (as was his wife and all of their kids). They are shown to be in South Sherbrooke Township in Lanark County, Canada West (Ontario).
In the 1861 census, they are in the township of Bedford. They are shown as living in a log house at the time.
In the 1871 census, William’s wife is listed as widowed, so William had passed away by then.