On the 1840 census Pettis County Missouri
there is a ROBERT FOWLER age:30-40 and a female:20-30
no children living with them. So Robert was born 1802 would be 38 years fits that column and Emaline born 1822 would be 18 years so that does NOT fit the 20-30 column and they did not marry until 1841..
So the theory that he was married previously is possible.
The Elizabeth L. Butler was born 1821 and is said to have died 1838 so this does not fit either. Unless her death date is incorrect. See Robert M. for the note

Missouri, Marriages, 1750-1920
NAME: Robert FOWLER
SPOUSE: Emily Jane Lee
DATE: 23 Sept. 1841
PLACE: Pettis Co. MO

1850 census Bowling Green, Pettis Co. MO
HEAD: Robert FOWLER age:49 Farmer KY
Emaline J. age:29 KY
Robert M age: 8 MO #77144837 Mar.: Nancy
Mary A. age:7 (aka Polly Ann)
Lewden age:5 MO
Lucinda age:2 MO
Emaline age: 1 MO

1860 census Grissom/next door Morrison
1860 June 10 census P.O.Georgetown, Bowling Green twshp, Pettis Co. MO
HEAD: Gresham Lee Sen. age:81 farmer born: E.Tenn. Robert FOWLER age:55 Farmer KY
Emily J. age:37 MO
Robert M age: 18 MO
Polly Ann (Mary A.) age:16 MO
Luden age:14 MO
Lucinda age:12 MO
Emaline age: 10 MO
Levisa age:6 MO (yob=1854
Hannah age:4 MO
Rhoduskia age:2 "F" MO **THIS MUST BE the SON
LODOSKY born SEPT 22, 1857
Grisham age:11/12
next door to them is
Morrison LEE age:30/Elizabeth,20/Ellen,8/James,6/Levisa,6/William,2
also next to them is Grissam Jr/Darrias/3 kids
NOTICE THAT JOHN/EMILY FOWLER NAMED A DAUGHTER LEVISA BORN 1854 AND MORRISON LEE/ELIZABETH'S DAUGHTER LEVISA WAS ALSO BORN 1854....OMG (Morrison's is my g-g-gramma

1870 June 23 census P.O.Arrow Rock, Blackwater twshp, Saline Co. MO
HEAD: Emily age:48 KY keep house
Luden age:24 MO
Lucinda age:22 MO
Emaline age: 20 MO
Lavitha (Levisa) age:17 MO (yob=1854
Hannah age:15 MO
Loduska (Rhoduskia) age:13 "M" MO
Grisham age:10 MO
James age:8 MO
Thomas age: 6 Mo
(husband Robert not listed...he was born 1801,believe deceased #22334520)
Their son? Lodoskey born 22 Sep 1857 D: 15 Jan 1875 age 17
#22334519 buried next to his father.

1880 census Heaths Creek, Pettis Co. MO
HEAD: Emily FOWLER age: 48 (58) KY Widow keep house
Lucinda age:22 MO (32)
Emeline age:21 (30)
Gresham age:21
Thomas age:16
Louden age 30 (34)
(MOST of the ages are incorrect... if you add 10 to the 1870 census)

'***********************************************************
CHILDREN:
Robert M B:1842 MO #77144837 Mar.: Nancy
Mary A. B:1844 (aka Polly Ann)
Lewden B: 1846 MO
Lucinda B:1848 MO
Emaline B:1850 MO
Elizabeth B:1852 MO
Levisa B:1854 MO
Hannah B:1856 MO
Rhoduskia B:1858 "F" MO AKA "M" son: LODOSKEY
Grisham B:1859
James B:1862
Thomas B:1864

1890 census NOT

1900 census
HEAD: Luden FOWLER age:55 born Jan 1845 MO/KY/KY
MOTHER: Emily J. Fowler age:78 born Feb. 1822 KY/KY/KY
and 1 brother and 2 sisters living with them.

And Diana pointed out that the 1900 census was there. This time I tried it.... came right up...Thank you again.
Thank you Diana for finding her headstone and giving us pics with the date of birth and date of death...