Hello True Brit, these are my thoughts.
WILLIAM SMITH BORN ABT 1833: Through all the censuses when he is married to Parthena Careless, he gives his place of birth mainly as Dudley, and Netherton (Netherton came under Dudley)
On FreeREG, I can see only one William Smith born about 1833 with no father’s name (the one you found on familysearch):-
Baptism: 28 July 1833 at St Thomas, Dudley
William – Mother: Mary SMITH – Abode: Dudley – Notes: Illegitimate
If this is the correct baptism, Mary could have married between the birth of William and the 1841 census! Which Mary Smith are we looking for!!
At the moment, FreeREG
http://www.freereg.org.uk covers baptisms for St Thomas’s, Dudley 1813-1859.
MARIA ELIZABETH EVANS/SMITH: From FreeREG
Baptism: 28 Mar 1875 at High Street Primitive Methodist Chapel, Bilston
Birth: 8 Mar 1875 – Maria Elizabeth – Abode: Smith Street – Father’s Surname: Evans – Mother’s Name: Lena (No father’s first name)
This looks very much as though Maria Elizabeth was illegitimate.
SELINA EVANS (Mother of Maria Elizabeth & Wife of John Smith):Baptism: 12 May 1857 at High Street Primitive Methodist Chapel, Bilston
Selina – Abode: Smith Street – Parents: William & Elizabeth Evans – Father’s occ: Miner
I found a Selina Evans on census living in Smith Street, Bilston, with parents William & Elizabeth (which could be the correct one) but William & Elizabeth’s births are different in census:-
1861 Census – 33 Smith Street, Bilston
William Evans – Head.M – 33 – Boatman – Sellatyn, Salop (born c1828)
Elisabeth Evans – Wife – 38 – Bickford, Salop (born c1823)
Charles Evans – Son.UM – 18 – Boatman – Braden Heath, Salop (born c1843)
Martha Evans – Dau – 7 – Scholar – Bilston (born c1854)
Selenia Evans – Dau – 4 – Scholar – Bilston (born c1857)
1871 Census – Smith Street, Bilston
William Evans - Head.M – 52 – Forge Labourer – Knockin, Salop (born c1819)
Elizabeth Evans – Wife.M – 57 – House Duties – Ellesmere. Salop (born: c1814)
Charles Evans – Son.M (ditto written under above line) – 29 – Coal Miner – Welsh Hampton
Selena Evans – Dau – 13 – Scholar – Bilston
There’s also quite an age gap between the children Charles, Selina & Martha Evans.
I found John & Selina Smith in the various census, but still can’t find Selina in the 1881 census.
Best to wait until you receive the marriage certificate for Selina Evans and John Smith:-
Marriages Jun 1876
John Smith & Selina Evans Wolverhampton 6b 647
NL - Before the census info goes on to BCC I think it's best for True Brit to wait for the above marriage cert.