In the 1850 US Census for Keokuk, Lee County, Iowa the family of Ross B. Hughes was enumerated as follows:
Dwelling #727; Family #733
R. B. Hughes, 40, M, W, Merchant, b. Maryland
Marietta Hughes, 27, F, W, b. New York
Henrietta Hughes, 11, F, W, b. Missouri, Attended school within the census year
Ross Hughes, 7, M, b. Iowa, Attended school within the census year
Josephine Hughes, 6, F, b. Iowa, Attended school within the census year
William Hughes, 3, M, b. Iowa
Eveline Barnum, 24, F, W, b. New York
William R. S. Duggree, 40, M, W, Physician, b. New Jersey
Abram Dugrree, 29, M, W, Clerk, b. New Jersey
[Note: living next door was the family of David B. Hughes, possibly a brother of Ross].
Given the age of Henrietta and the age of the next oldest child in the 1850 census, it is possible that Ross was previously married and that Henrietta was born of that union. In the 1850 Census Ross states that he was born in Maryland. There is a record for a marriage between a Ross Hughes and a Mary Nusz that took place on November 29, 1829 in Frederick County, Maryland.
From the Mount Pleasant Weekly News, Mount Pleasant, Iowa, September 13, 1899: Early Life in Iowa. Married in Haste. Ross B. Hughes, a citizen of Keokuk, in 1848. He had the largest cooper shop west of Cincinnati. It burned down January 3, 1848. In ten days it was restored, and the event was celebrated with a dance. During the festivities, he being a widower, Hughes dared any one present to marry him. A tall, good looking girl, Miss Barnum, accepted his offer. He sent for a minister and they were married in about fifteen minutes. He some time after went to California. They lived happily together. At one time he was a steamboat captain on the Mississippi. He had daughters who were wives of some of our very prominent men, among whom was George H. Williams. Before they were married, he being a judge granted her a divorce. If I remember correctly, he was a senator from the state of Oregon at one time. He died in Saint Louis.