1850 Federal Census for Berlin, St. Clair County, MI has Edward Spear 26 born Canada, farmer, and Charlotte 25 born Canada with Elizabeth 6 born Canada and Calvin 1 born Canada. Next door is Nelson Spear 24 born Canada and Sarah 20 born Canada and Andrew J. 1 born MI
on other sides is CALVIN SPEAR 50 born Canada, Charlotte 40 born Canada with Elijah 10, John 8, Nancy 6, Gideon 3 all born CANADA and Hannah 2 months born in MI.

There is confusion between Elijah son of Calvin, and Calvin son of Edward Lysum. They are not the same person.

CALVIN COULD BE AN UNCLE AS EDWARD AND NELSON ARE OLDER THAN CALVIN’S ELIJAH WHO IS JUST 10 IN 1850
indication on Ancestry Trees that Edward is half-brother to Nelson, Horace and Nancy

Calvin Spear md 1822 Charlotte Stone in Gariot MI. He dies 1853 and His son Edward 1824 adm. will. Edward the brother of Nelson 1826.
Seems to be Calvin Edwin Spear in census 1850 in Berlin, St. Clair, MI