Beyond the surname, it's not clear that there is any connection between Hart and Dwight and the William Mickle descendants:
Article, Amherstburg Echo, 9 June 1911:
The Mickle Family - Re Union of One of Essex County's Historical and
Influential Families:
The Mickle family reunion was held on Bois Blanc Island, on Wednesday last, June7th. The gathering was attended by family coming from all parts, some coming from the Pacific coast, and many from the states of the Union, but Essex, Kent and Lambton were particularly well represented...
... the chairman called upon Henry Mickle, who welcomed them all and gave a short address in which he referred to William Mickle as the original head of the Mickle clan, who had come from Aryshire, Scotland, before the American revolution. About 1793 he was engaged in the construction of the British Government navy at Fort Malden and later at York (now Toronto), where he died of typhoid fever. He said there were about 600 descendents...
The register showed the following to have signed the book: ...
Hart Mickle, wife and sons Dwight and Glen, of Cass City, Mich...
Dwight
Mickle
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