Based on information you have provided in your family tree, as well as information obtained from ancestry.com and familysearch.org, it appears the great-grandfathers of your father are:
(1) James Morgan, born in Virginia abt. 1802 (see previous G2G)
(2) the unknown father of Mary Lane (married to William F. Morgan), born in Virginia according to Mary's 1880 and 1910 censuses
(3) William McCluney Creighton, born abt. 1817 in Virginia
(4) the unknown father of Sarah P. Bunt/Burt/Bent (who herself was born in Ohio abt. 1841 but has not been traced before her marriage in 1865 to Alexander Creighton), born in Germany according to Sarah's 1880, 1900, and 1910 censuses.
Of these, the fourth is an obvious candidate for someone who "came over on the boat", though it seems hard to reconcile "Schoonover" with "Bunt/Burt/Bent"