Spoon Decora stated, "I am the nephew of Big Canoe; and Doc Decorah the medicine man, who lives near me, is my nephew. Doc's father, who was named Bad-Spirit Killer, was my brother-in-law." (Thwaites, 461)
Spoon's wife was Gray Eyes. We may deduce that Bad-Spirit Killer and Gray Eyes were siblings, and therefore had the same parents. We do not know the name of their father, but the surname "Gray Eyes" was used since "Gray Eyes" was treated as a last name for Spoon's wife.
If Gray Eyes the wife of Spoon was the product of a traditional marriage, she would have to have belonged to the opposite moiety, as marriages are cross-moiety. Given that the Decoras belonged to the Upper Moiety, it follows that his wife belonged to the Lower or Earth Moiety. Moieties are patrilineal, so the father whom we are calling "Gray Eyes" here, will have been of the Lower Moiety.
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