From what I can see the surname Brown doesn't appear in this family prior to 1860.
William Sexton married Elizabeth Anstee 29 Mar 1824 Ivinghow Buckingham.
- Banns read in St Mary Hemel Hempstead say William Sexton, bachelor, was "of this parish" & Elizabeth Anstee, spinster, was of the parish of Ivinghow Buckingham
Wm & Eliz Sexton are recorded, with their children, on all census with surname SEXTON. Both died as Sexton.
First recorded ref I've seen was 23 Dec 1860 when George Sexton Brown married Caroline Henrietta Powell. George said his father was William Sexton Brown. (noted earlier)
1861 census - It seems that George hasn't yet got the hang of using his new name as 1861 census has George B. Sexton & Caroline Sexton Hemel Hempstead (presume the "B" was for Brown)
- Their children were registered with second forename as Sexton, surname Brown.
Thereafter, the family surname for George & his descendants was Brown.
I initially thought that the name change could be a family disagreement or something that caused George to "disown" his family/name but then found that 2 of his siblings, Edward & Eliza also married with their surname as Brown.
1867 - Edward Sexton Brown married Margaret Dagley & Eliza Sexton Brown married Walter Rance (possibly) same date & place 24 Jan 1867 - Baptist Chapel, Hemel Hempstead.
- Edward Sexton Brown registered his children with surname "Sexton". All census say his name was Sexton. So looks like whatever happened in the 1850's ,causing the surname change, had been resolved.
- Mother's maiden surname on Eliza & Walter Rance's children was Sexton.
Neither Edward or Eliza appear to have used the surname Brown before or after their marriage day
Apologies for repeating previous posted info - just trying to get a timeline.
