How did you find Ann Batt in the 1851 census?
I just searched surname 'Batt' place 'Taunton' in the 1851 dataset

HO107
Piece 1922
Folio 544
Page 8
Living Batts Court, High Street, Taunton
Ann Batt 41 -Annuitant
Her children -
William J 16 - Cabinet maker apprentice
Henry 15 - Tailor apprentice
Maria Emily 9
Charles 5
Elizabeth Chapple Servant 20 House servant
All born Taunton
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Birth registrations
BATT, MARIA EMILY mmn WYATT
GRO Reference: 1842 March Quarter in TAUNTON Volume 10 Page 495
BATT, CHARLES mmn WYATT
GRO Reference: 1846 June Quarter in TAUNTON Volume 10 Page 475
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In 1841 she is with probable husband William and son Henry at Mount Street, Taunton. William was a coachmaker