Commemorative Biographical Record of Essex Co., p. 308-313:
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William McCormick ... on Jan. 29, 1809, married a member of one of these families, Mary Cornwall, who was born in the County of Essex, July 22, 1792. They settled on the old homestead farm, ...
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Mr. and Mrs. McCormick were the parents of thirteen children, two of whom died young, the other eleven with his aged mother and maiden sister, Betsy, moving to Pelee Island with him. We have the following record of his family: A daughter, born Dec 12, 1809, died in infancy; ...