Individual Details

Kentucky Marriages, 1802-1850, database at Ancestry.com, has a marriage for Mary Dickerson to John Sergent, 2 May 1809, Campbell Co KY. They were married by Thos. Griffing. This date when compared with the 1850 census is a bit confusing - they would have been only 13 years old when they married which is highly unlikely. They had probably lost track of their ages by 1850.
A descendant with a family tree on Ancestry has given her a birth year of 1791. However, this date of birth is also found in a file on WorldConnect that has erroneously placed Mary in a very different family.

There were more children in this family than I have been able to identify.

1830 Census. Boone Co IN
John Sergent: 1m under 5, 2m 5-10, 1m 20-30, 1m 30-40
1f under 5, 1f 5-10, 1f 10-15, 2f 15-20, 1f 30-40

1840 Census. Boone Co IN
John Sergent: 1m under 5, 1m 5-10, 2m 15-20, 1m 40-50.
1f 10-15, 1f 20-30, 1f 40-50

1850 Census. Dist 7, Boone Co IN Hh 1476
John Sargeant, age 54, b. VA. Mary, age 54, b. KY
Children living with John and Mary in 1850 appear to be: Robert age 25, Alexander age 19, and Oliver age 14 - all born in Indiana

Mary is said to have died 1870 in Warren, KY, but I've not found John or Mary after 1850.

Birth	1794	Kentucky
Marriage	2 May 1809	Campbell County, Kentucky - John Sargeant

Spouse	John Sargeant (1790 - )
Child	Samuel Sargent (1812 - )
Child	Robert Sargeant (1825 - )
Child	Mary Ann Sargent (1827 - )
Child	Alexander Sargeant (1831 - )
Child	Oliver Sargeant (1836 - )

Father	ROBERT DICKERSON (1759 - 1829)
Mother	NANCY BOOTH ( - )
Sibling	William Dickerson (1792 - 1840)
Sibling	Sarah Dickerson (1793 - )
Sibling	Alexander Dickerson (1796 - 1875)
Sibling	PHILADELPHIA DICKERSON (1797 - 1847)
Sibling	Drusilla Dickerson (1802 - 1879)
Sibling	Ruth Dickerson (1803 - 1866)