The route back to my new found Duxburys........

Samuel Smith m Elizabeth Alice Thornber, 1883 Blackburn (my great-grandparents)
Elizabeth Alice Thornber, b1863 at 13 Eccles Street, Blackburn
dau of Ralph Thornber & Ann HARGREAVES (my gr.gr.grandparents)
Ann HARGREAVES m Ralph Thornber, 1862 Blackburn

Ann Hargreaves, b1842 in Darwen, was the dau of
John HARGREAVES & Betty DUXBURY (my gr.gr.gr.grandparents)
The 1841 & 1851 Over Darwen Census and 1861 Blackburn Census
all confirm that Betty was born in Darwen c1816
>>Census data on my Hargreaves Topic>>

Marriage of John Hargreaves and Betty Duxbury:
from LancashireBMD Index:
Blackburn marriages:1839 St Mary the Virgin (Blackburn Cathedral)
HARGREAVES John / DUXBURY Betty
Blackburn Reg Office Ref: CE12/1A/362

I haven't got the marriage certificate yet, but......
Matching entries in the GRO Indexes narrow it down to quarter year....
1839 July-Sept Quarter: Blackburn Reg District :
GRO Vol 21/page2 : Hargreaves John / Duxbury Betty

Matching entry in IGI Batch No M007086 1831-1846, narrow it down to the date......
7th July 1839 St Marys Blackburn
JOHN HARGREAVES / BETTY DUXBURY

Until I've checked the marriage record to confirm Betty's father's name, and also the Darwen Lower Chapel Baptism Register, it's looking very likely that the following IGI births & Christenings entries are for my Betty and her siblings:

Over Darwen Lower Chapel (IGI batch C133071 1751-1837)
All children of Thomas DUXBURY & Ann BRIGGS (??my gr x 4 grandparents)
Betty Duxbury - Birth: 26 Aug 1816 Christening: 06 Nov 1816
John Duxbury - Birth: 04 Mar 1819 Christening: 24 Apr 1819
William Duxbury - Birth: 04 Nov 1823 Christening: 19 Feb 1824
Jane Duxbury - Birth: 19 May 1826 Christening: 24 Apr 1828
Timothy Duxbury - Birth: 27 Apr 1829 Christening: 24 Nov 1830
Thomas Briggs Duxbury - Birth: 31 Aug 1833 Christening: 08 Oct 1833

That's where I'm up to with my Duxbury's so far.
But I'm going to explore this website..........
Darwen - Duxbury family History