Good evening Maddie,
Since yours is a simple question, I can make a simple answer. As is normal (essential) in family history research, I first worked backwards and then sideways. This went from Matilda Brown (Christened 1813, dd 1895), then back to her father, Daniel Brown (Christened 1784 - dd 1864) who married Ann Gates in London in 1812. Daniel's father was William Brown, who married Sarah Austin in Chenies in 1778. I have children in Chenies from both these marriages. I also followed a number of "blind alleys" with Brown families while searching and figuring out which were "my" line. These included a couple of bits that look relevant to you.
First, from the 1992 IGI I have a note that Henry Browne married Sophia Marriott in Rickmansworth, 14/8/1811.
Then in Chenies Parish Register christenings, page 9, entry 70, I have 1818, Aug 2, Henry son of Henry & Sophia Brown of Chenies, paper maker. Nothing else noted for Henry right up to 1854.
Henry Brown and Mary Crutch both of Chenies married by Banns on 25 May 1820 (Phillimore has 21/5/1820). Both made a mark. Witnesses: Abraham Brown, Lucy Brown, William Beeson (Clerk).
I guess you already have this information, so I'm sorry that my records are of no help to you.
Just one possible place to look is Flaunden, Herts, because there seem to have been links to Chenies from time to time.
Kind regards,
George Dickinson.