Thanks so much for pursuing this further by finding what well might be the correct Stevensons, this time in the nearby village of Quorndon. Let me give a couple of reasons why it might well be the right one. First, the christening date for the baby is only a month shy of 1806. The mother's name is Elizabeth. If that baby also called Elizabeth was an only child it might account for why she has not only her 70 year old mother living with her in 1841 in Tiverton but also has her husband's mother of the same age (Mary (Worth) Bennett.
It's also revealing how William Worth Bennett and Elizabeth named their Devon children born between 1826 and 1840. The first, William Cuthbert Bennett (named after her husband.) Second is John Stevenson Bennett (named for her father.) which would match this record you found. Third is Josiah Worth Bennett (second name for William's mother's family.) Selena Wesley (assumed to be named for John Wesley since there's a strong methodist link moving forward.)
Assuming John Stevenson moved his family to Tiverton with Heathcoat, he would have died prior to the 1841 census which I know complicates things. I assume he died in the town so there must be a record of his death? Also I'm still really curious about what he did for a living. Based on your experience of following these leads, is there any way to find that out? Would his occupation be on Elizabeth's birth certificate or his death certificate?
Last, John Stevenson was in all likelihood a methodist, does that change the search for these records in Loughborough or Tiverton? Would it be more likely there wouldn't be earlier Stevenson gravestones in that village C. of E. churchyard in Quorndon?
