Hi,
I've found this possible marriage for Charles King and Sarah, I'll start with her baptism and possible first marriage as I find that an easier way to explain my findings

England, Pallot's Baptism Index, 1780 - 1837
MISKIN Sarah
(Wm-Royal Horse Artillery & Mary nee PETTS)
Woodbridge Suffolk 1799
Found here,
http://essexandsuffolksurnames.co.uk/parish-register-transcriptions/essex/east-donyland/East Donyland (Rowhedge) St. Lawrence
19 Feb 1823
BROWN James bachelor
MISKIN Sarah spinster
Witnesses: William BROWN, Mary Ann BANKS
and
27 Sep 1831
KING Charles bachelor
BROWN Saran Ann widow
By banns. Mary ALDRIDGE, James KING, Mary CHEEK
It looks like James BROWN and Sarah have a daughter,
East Donyland St. Lawrence
14 Sep 1823
BROWN Harriet Rebecca
Parents: James & Sarah Fisherman
In 1841 there is a Harriet BROWN living in the same premises as Charles and Sarah KING.
The only way to be sure would be to get the birth cert. of their daughter Ann,
Ann KING Sep Q 1840 Lexden 12 121
Regards,
Daisy