1.  Anon.  1966.  Marriage Index:  Ohio, 1789-1850.  Liahona Research, Orem, UT (Broderbund CD-400):

Kerstetter, John

Hershberger, Catherine

14 Feb 1826

Stark Co.

2.  1830 Census Index and Digital Images (online at Ancestry.com; Image #15 of 15; extracted by Diana Gale Matthiesen):

1830

OH

Stark Co.

Green Twp.

p. 337

John Castetter

100 110 - 000 010

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	4 or under	1825-1830	= Son A
1 male	15-19	1810-1815	= ?
1 male	20-29	1800-1810	= John (b. 1805)
1 female	20-29	1800-1810	= Catherine (b. 1804)

The teenager is too old to be their child; he could be kin or hired help.

3.  1840 Census Index and Digital Images (online at Ancestry.com; Image #17 of 18; extracted by Diana Gale Matthiesen):

1840

OH

Summit Co.

Green Twp.

p. 313

John Castater

111 101 - 220 001

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	4 or under	1835-1840	= Samuel (b. 1839/40)
1 male	5-9	1830-1835	= Son B
1 male	10-14	1825-1830	= Son A
1 male	15-19	1820-1825	= ?
1 male	30-39	1800-1810	= John (b. 1805)
2 females	4 or under	1835-1840	= Mary (b. 1835/6) = Daughter C
2 females	5-9	1830-1835	= Daughter B = Daughter A
1 female	30-39	1800-1810	= Catherine (b. 1804)

Another teenager too old to be their son.  More hired help?

4.  1850 Census Images (online at Ancestry.com; Image #509 of 731):  District 140, Green Twp., Summit Co., OH, p. 16B, 3127/3150, enumerated 22 Nov 1850 (extracted by Diana Gale Matthiesen):

John Castetter	45	M	Carpenter	3200	Penn
Catharine Castiter	46	F			Do
Mary Castiter	14	F			Ohio
Samuel Castiter	10	M			Do
Susannah Castiter	8	F			Do
Daniel Castiter	5	M			Do
Elizabeth Castiter	20	F			Do
Emanuel Castiter	?	M			Do

Whatever Emanuel's age was, it was a single digit, probably 1 or 3.  The question here is whether Elizabeth is out of order deliberately or mistakenly.  If deliberately, it indicates she is not their daughter — a niece or widowed daughter-in-law, perhaps — and that Emanuel is Elizabeth's son.  If Elizabeth is out of order inadvertently, then it is no stretch for her to be our subjects' daughter as they had a daughter in that age class in the household in 1840.  Also, Catharine is not so old that she couldn't be the mother of Emanuel.

5.  1860

6a.  Family Quest Archives:  Indiana 1870 Census Index.  Heritage Quest ACD-0038:

Surname	Given name	Age	Sex	Race	Birth Place	County	Locality	Roll	Page
Castetter	John	64	M	W	PA	Elkhart	Elkhart	311	311
Castetter	Samuel B	30	M	W	OH	Elkhart	Elkhart	311	311
Casteter	Daniel	40	M	W	OH	De Kalb	Union Twp	309	404
Castetter	John J	40	M	W	OH	Kosciusko	Warsaw	332	124
Castetter	Carrie	18	F	W	OH	Kosciusko	Warsaw	332	115
Castetter	B	22	M	W	IN	Madison	Anderson	336	65
Castetter	Frank	20	M	W	IN	Boone	Jackson Twp	300	133

6b.  1870 Census Images (online at Ancestry.com; Image #44 of 80):  Elkhart P.O., Elkhart, Elkhart Co., IN, p. 311B, PN 84, enumerated 3 Aug 1870 (extracted by Diana Gale Matthiesen):

1870:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).
1	2	3	4	5	6	7	8	9	10	17	19
396	415	Castetter John	64	M	W	Carpenter	8800	2000	Pennsylvania		/
		_________ Catharine	66	F	W	Keeping house			Pennsylvania	/

Living next door to son, Samuel B. CASTETTER.