This may be Curtis and Nancy on the 1880 census but the names of the children are so different that I will not add them, pending further research.
Curtis POWEL Self M Male W 37 MI Farmer MA NY
Nancy POWEL Wife M Female W 34 MI Keeping House OH VA
Perry POWEL Son S Male W 10 MI At School MI MI
Jennie POWEL Dau S Female W 8 MI At School MI MI
Wilber W. POWEL Son S Male W 5 MI MI MI
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Source Information:
Census Place Porter, Cass, Michigan
Family History Library Film 1254575
NA Film Number T9-0575
Page Number 581C