Hi
Is this the Stevens family you are looking for?
1841 census Fonthill Gifford HO107/1175/7
James Stevens, aged 30, ag lab. born in County
Mary Stevens, aged 30, born in County
Frederick Stevens aged 10, born in County
Priscilla Stevens, aged 8, born in County
Maria Stevens, aged 5, born in County
John Stevens aged 90, born in County
All living in the same Household. There was no other Mary Stevens of the right age living in Fonthill Gifford at the time of the census.
Hope this helps
Mary