Here she is in 1841:
Bristol St Michael, Bristol Steps (No number)
William Rossiter 27 Painter Born in County
Mary " 25 "
Catharine " 4 "
HO107/373/8
No sign of any siblings. Father William died in 1845 - Catharine married in Bath, 1858 - I can't locate them in 1851 yet - I'll keep looking.
Regards,
Lee
I have an 1851 census entry as follows
St. Michael's
THORNHILL PLACE
FEAR Robert 27 Warehouseman Bristol Temple
Mary 35 Cap Maker Bristol Temple
COCKS James wifes son 16 Tea man St Pauls, Bristol
Emma Wifes Daughter 14 Waistcoat Maker Redcliffe
Edward wifes son 9 City School boy Bristol St James
*
ROSSITER Mary 38 Dressmaker St Pauls, Bristol
Catherine 15 Milliner Bristol St James
No sign of William Rossiter