1a.  Works Progress Administraton.  1938-40.  Index to Marriage Records: Indiana (online at Ancestry.com):

Charles A. Gilbert

Lovina Hackett

17 May 1881

Lagrange Co.

Bk. 5, p. 37

1b.  LDS.  Family Search: Internet Genealogy Service: Pedigree Resource File (index to CDs, online at FamilySearch.org).

Charles A. GILBERT Birth: 09 Sep 1854, Lima, Adams, Illinois Father: Austin GILBERT; Mother: Juliett ALGEIER Marriage: Lovina HACKETT

I don't know where they got the idea Charles was born in Illinois because Austin was living in LaGrange from at least 1850 onwards.

2.  1890 Census:  the 1890 Census Population Schedules were destroyed.

3.  1900 Census Every-Name-Index/Images (online at Ancestry.com, Image #10 of 20):  Springfield Twp., LaGrange Co., IN, Roll T623_383, p. 144B, SN 5, SD 12, ED 79, enumerated 11 Jun 1900, official enumeration date 1 Jun 1900 (extracted by Diana Gale Matthiesen):

1900:  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

11

12

13

14

15

19

20

21

22

23

24

25

26

27

28

122

125

Gilbert Charles A

Head

W

M

Sep 1855

44

M

19

IN

OH

VT

Farmer

0

Y

Y

Y

O

F

F

79

_______ Elvira S

Wife

W

F

Jan 1863

37

M

19

3

3

MI

NY

WI

Y

Y

Y

_______ Gladys L

Dau

W

F

Aug 1882

17

S

IN

IN

MI

At School

9

Y

Y

Y

_______ Bessie L

Dau

W

F

Mch 1884

16

S

IN

IN

MI

At School

9

Y

Y

Y

_______ Carl D

Son

W

M

Jul 1890

9

S

IN

IN

MI

9

Y

Y

Y

4.  1910 Census Index/Images (online at Ancestry.com, Image #13 of 30):  Springfield Twp., LaGrange Co., IN, Roll T624_361 (Part 1), p. 198A, SN 7A, SD 12, ED 103, enumerated 23 Apr 1910, official enumeration date 15 Apr 1910 (extracted by Diana Gale Matthiesen):

1910:  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

11

12

13

14

17

18

19

20

23

24

25

26

27

28

29

115

115

Gilbert Charles A

Head

M

W

55

M1

28

IN

IN

IN

Eng

Farmer

General farm

OA

Y

Y

O

?

?

?

_______ Vira

Wife

F

W

48

M1

28

3

2

MI

NY

WI

Eng

None

Y

Y

_______ Karl D

Son

M

W

19

S

IN

IN

MI

Eng

None

Y

Y

Y

Stroup, Gilbert M

GSon

M

W

6

S

IN

IN

IN

None

N

Gilbert is the son of their late daughter, Gladys (GILBERT) STROUP.

5.  1920 Census Index/Images (online at Ancestry.com, Image #10 of 20 — indexed "Charles U. Gilbert"):  Springfield Twp., LaGrange Co., IN, Roll T625_443, p. 61B, SN 5B, SD 12, ED 125, enumerated 8/9 Jan 1920, official enumeration date 1 Jan 1920 (extracted by Diana Gale Matthiesen):

1920:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).

2

3

4

5

6

7

8

9

10

11

12

16

17

18

19

21

23

25

26

27

28

29

Fm

113

116

Gilbert Charles A

Head

O

F

M

W

65

M

Y

Y

IN

OH

VT

Y

Farmer

General Farm

Em

81

_______ Vira

Wife

F

W

59

M

Y

Y

MI

NY

WI

Y

None

_______ Karl

Son

M

W

29

S

Y

Y

IN

IN

MI

Y

Laborer

General Farm

W

Miller Carl

Guest

M

W

17

S

N

Y

Y

IN

IN

IN

Y

None

6.  1930 Census Index/Images (online at Ancestry.com, Image #8 of 16):  Bloomfield Twp., LaGrange Co., IN, Roll 595, p. 243B, SN 4B, ED 44-1, SD 3, enumerated 14 Apr 1930, official enumeration date 1 Apr 1930 (extracted by Diana Gale Matthiesen):

1930:  for an explanation of the column headings, please see What the Numbers in the Federal Census Mean (missing columns contained no data).
3	4	5	6	7	9	10	11	12	13	14	15	16	17	18	19	20	24	25	26	27	28	30	32
96	96	Gilbert Charles A	Head	R	R	Y	M	W	76	M	29	N	Y	IN	OH	OH	Y	Farmer	General Farm	E	Y	N	89
		_______ Vira	Wife				F	W	69	M	20	N	Y	MI	MI	WI	Y	None