4.  Iantha CORBIN, b. 1842/3
5.  Martha Ellen CORBIN, b. 1845/6
6.  Ferdinand CORBIN, b. 1848/9

— born in Huntingdon Borough, Huntingdon Co., PA:
7.  Stephen / Stephens / Stevens Garfield CORBIN, b. 1850/1/2/3; d. 20 Dec 1879, Altoona, PA 
8.  Alice A. CORBIN b. 1856
9.  Elmer E. CORBIN, b. 1862

Are Nancy and Iantha the same individual?  Are Iantha, Martha Ellen, and Ferdinand really their children?  (See 1850 and 1860 census records, below.)

1.  Marriage Record:

2.  1840 Census Index and Digital Images (online at Ancestry.com; Image #7 of 10; extracted by Diana Gale Matthiesen):

1840

PA

Huntingdon Co.

Union Twp.

pp. 266B-267A

Ferdinand Corbin

100 010 - 000 010

0001000

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	4 or under	1835-1840	= William (b. 1837/8)
1 male	20-29	1810-1820	= Ferdinand (b. 1819/20)
female	20-29	1810-1820	= Martha (b. 1819/20)
1	person engaged in manufacture and trades

Listed 11 lines below Caleb CORBIN and six lines above Caleb GREENLAND, who is one line above Nathan GREENLAND, who is one line above Israel GREENLAND.

3.  1850 Census Index/Microfilm (online at GenealogyLibrary.com):  Huntingdon Borough, Huntingdon Co., PA, p. 43, 29/32, enumerated 20 Aug 1850 (extracted by Diana Gale Matthiesen):

Ferdinand Corbin	30	M	Boatman	Penn
Martha      "	30	F		"
William     "	12	M		"
Lucrecia    "	9	F		"
Nancy       "	7	F		"

Where are Iantha, Martha Ellen, and Ferdinand?!

4.  1860 Census Images (online at Ancestry.com; Image #27 of 49):  Huntingdon P.O, Borough of Huntingdon (eastern half), Huntingdon Co., PA, p. 321, PN 9, 62/63, enumerated 5 Jun 1860, official enumeration date 1 Jun 1860 (extracted by Diana Gale Matthiesen):

Ferdenand Corbin	40	M		Labourer	350	70	Penn
Martha Corbin	39	F					"
Iantha	17	F		Seamstress			"
Martha Ellen	14	F					"
Ferdenand	11	M					"
Stevens G	9	M					"
Alice A	4	F					"

Are Iantha, Martha Ellen, and Ferdinand really their childred?  Were they simply missed in 1850?

5.  1870 Census Images (online at Ancestry.com; Image #2 of 18):  Huntingdon P.O., Henderson Twp., Huntingdon Co., PA, p. 608B, PN 2, 14/17, enumerated 28 Jul 1870, official enumeration date 1 Jun 1870 (extracted by Diana Gale Matthiesen):

Corbin Ferdinand	51	M	W	Farmer			Penna
______ Martha	50	F	W	Keeping house			Do
______ Stephens	18	M	W	At home			Do
______ Alice	13	F	W	At home			Do
______ Elmer	8	M	W	At home			Do
Mick Renbow	24	M	W				Do

Living next door to Henry HIGHT. 

6.  1880 United States Census and National Index (LDS Family History Resource File: CD-ROM Library):

Census Place: Huntingdon, Huntingdon, Pennsylvania
Source: FHL Film 1255134; NARA Film T9-1134; Pg 170C
	Relation	Sex	Marr	Race	Age	Birthplace	Occupation	Fa	Mo
Martha CORBAN	Self	F	W	W	60	PA	Keeping House	PA	PA
Elmer E. CORBAN	Son	M	S	W	17	PA	Working In Mines	PA	PA