1841 Mary Parker is not born in Northumberland.
Bapts;
St Mary, Gateshead, Durham
RALPH POTTS Parker 09 Mar 1822, buried 24 Mar 1822 sage 14 days
MARY Parker 16 Nov 1823*****
Parents as WILLIAM/ISABELLA, Father a Gardener, abode Gateshead
(FreeREG)
1821 Marriage is there also, it implies William could write as Isabella signs X
Its appears to me that Daug Sarah married a James ORWIN 1869
1871 Census
James Orwin 30 Head
Sarah Orwin 38 Wife
William Orwin 8 Son
Isabella Orwin 5 Daughter
Michael Orwin 27 Lodger
Trish

EDIT;
SARAH Parker bapt 1 Jan 1829 Wallsend, Northumberland
Birth 17 Oct 1827***
Parents WILLIAM/ISABELLA nee Potts
(F/S.Org)