You might want to look at Michael Caldwell's page. Go to Hayden (descendants), click on child #6, Abigail and and look for Isaac HUNTSMAN. He married Caroline HUNTSMAN, a cousin. However, this Isaac may not have been born on the Isle of Guernsey, nor was Caroline. This Caroline was the dau of John and Alice LINDER KINNEY HUNTSMAN. It is possible this Isaac was son of Mark HUNTSMAN and Ellen, who lived in Noble Co OH in 1860, and here is the Isaac who married Caroline Cassandra HUNTSMAN in 1880.
1880 OH Census: Guernsey Co. Millwood Twp. ed 73, p. 1, lines 19-26
Series T9, roll 1020, dwelling 5, family 5, 7 June 1880
Isaac W. HUNTSMAN, 41, Married, Laborer, has Rheumatism, b. Ohio, parents b. Ohio
Caroline, 37, Wife, Married, Keeping house, b. Ohio, parents b. Ohio
John W., 16, Son, Farm Laborer, school; Mary H., 15, dau, school
Laura M., 11, dau, school; Alta J., 7, dau, school
Emmer C., 10/12, b. July, son; Elmer D., 10/12, b. July, son