By way of clarification , here is Mary Ann Minear in 1861:
Piece: RG9/1549 Place: St Austell -Cornwall Enumeration District: 18D
Civil Parish: St. Austell Ecclesiastical Parish: -
Folio: 10 Page: 13 Schedule: 87
Address: Priory Row
Surname
First name(s)
Rel
Status
Sex
Age
Occupation
Where Born
Remarks
MINEAR William Head M M 36 Journeyman Tailor Cornwall - St Austell
MINEAR Rebecca (Hore) Wife M F 27 Tailor's Wife Cornwall - St Austell
MINEAR Elizabeth Jane Hore Dau U F 6 Scholar Cornwall - St Austell
MINEAR William Edw Son U M 4 Scholar Cornwall - St Austell
MINEAR Ellen Dau U F 2 Scholar Cornwall - St Austell
MINEAR Catherine Dau U F 1 Cornwall - St Austell
MINEAR Ann Visitr W F 24 Iron Monger's Widow Cornwall - St Agnes
Page: 10/14 MINEAR Annie Visitr U F 1 Cornwall - St Agnes
MINEAR Mary Ann Sister U F 21 Cornwall - St Austell
I think this means she was a sister of William John Minear.
The Mary Minear bpt 6 Apr 1834 ( base child of Jane )was apparently a sister ( she married William Henry Harry April 1853 St Austell ).Two different people so far as I can see.
Still no bpt found for Mary bC1840. Transcribed as "Mincer" 1841 and 1851
Sorry if still causing confusion.