"C." may be the first letter of Emma's maiden name, not her middle initial.

1.  Marriage Record:

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

3.  1900 Census Index/Images (online at Genealogy.com, Image #6 of "unknown"):  Washington Twp., Whitley Co., IN, p. 165B, SN 3, SD 12, ED 120, enumerated 6 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

64

66

Chamberlin John M

Head

W

M

Aug 1861

38

M

15

IN

OH

OH

Farmer

0

Y

Y

Y

O

M

F

54

__________ Emma C

Wife

W

F

May 1861

39

M

15

5

4

IN

OH

OH

Y

Y

Y

__________ Elzie L

Dau

W

F

Mar 1887

13

S

IN

IN

IN

At school

7

Y

Y

Y

__________ Doris M

Dau

W

F

Nov 1891

8

S

IN

IN

IN

At school

8

Y

Y

Y

__________ Walter G

Son

W

M

Sep 1894

5

S

IN

IN

IN

__________ Brice D

Son

W

M

Sep 1899

8/12

S

IN

IN

IN

Penn Samuel

Servant

W

M

Dec 1881

18

S

IN

OH

OH

Farm laborer

7

Y

Y

Y

Listed five households from Samuel's parents, Joseph & Harriet (CUPP) PENN.