— born in Muhlenberg Co., KY:
3.  Eugene W. MANN, b. 1838/9
4.  Elizabeth MANN, b. 1840/1 
5.  Aurelius MANN, b. 1832/3
6.  Martha M. MANN, b. 1844/5
7.  Herbert B. MANN, b. 1846/7

1.   Jordan R. Dodd, ed.  1993.  Virginia Marriages:  Early to 1850.  Liahona Research, Orem, UT (Broderbund CD-229):

Mann, Thomas N.

Walker, Judith S.

Sep 11, 1826

Amelia Co.

2. Census Index:  U.S. Selected Counties, 1830 (Broderbund CD-315):

1830	Mann, Thomas N.	TN	Fayette Co.	p. 31
1832 (tax list?)	Mann, Thomas N.	TN	Fayette Co.

3. Census Index:  U.S. Selected Counties, 1840 (Broderbund CD-316):

1840

Mann, T.N.

KY

Muhlenberg Co.

p. 344

4.  1850 Census Index/Microfilm (online at GenealogyLibrary.com):  Sub-division 2, Muhlenberg Co., KY, p. 247AB, 316/316, enumerated 6 Sep 1850 (extracted by Diana Gale Matthiesen):

Thomas N Man	47	M	Carpenter	Va
Judith	45	F		Do
George H.	18	M	None	Tenn
Thomas E.	16	M	None	Do
Eugene W.	11	M		Ky
Elizabeth	9	F		Do
Aurelius	7	M		Do
Martha M. Man	5	F		Ky
Herbert B. Man	3	M		Do
Susan Reaves	21	F		Do

Susan could be their widowed/divorced/deserted daughter, though I can't find a marriage in Muhlenberg Co. for a Susan MANN and a Mr. REAVES/REEVES.