Bacon Family from Petersfield ~1800

[RobHam]

One of my direct Ancestor lines links to a family from Petersfield.
Researching these boarder locations seems quite difficult because families and individuals keep jumping across the county boarder.

Thomas Bacon and wife Mary
with children
George      b. 1799
Mary         b. 1802
William      b. 1803
Lydia         b. 1804
Ann Maria   b. 1807   (direct ancester)
James        b.  1807

I have a record of the christenings.

I am keen to research two things as follows :-
1. The 1851 census has a Thomas Bacon born Petersfield 1797 so most probably he is an older child. Hence trying to track down his christening.

2. Also keen to track down the marriage of Thomas Bacon and Mary.
The Sussex marriage index has no likely candidates hence probably married in Hampshire