I have a spare copy of the marriage certificate of William Feakins and Ann Burrows, which I bought in 1979 whilst looking for the marriage of my ancestors William Feekings and Ann Baldwin, who married at Frindsbury, Kent on 29 Nov 1835, and whose children were all born at Higham, Kent. In the 1881 Census my Great-great-grandmother Ann is listed as Ann Feekins, Widow, 65, living at Cobham College (an Almshouse), with her grandson William Alfred Feekins, who by coincidence was born at Deptford.
In the 1851 Census for Deptford there is a Feakins family on Piece HO107/1584 at folio 266, reverse side. This ties in well with your family details which seems to be based on christenings, but with the addition of children Henry and Amelia.
The following two children were christened at Worth, Sussex, to William and Ann Feakins. Henry on 22 Jul 1838 Amelia on 22 Dec 1839 Also George on 5 Sep 1841 to George & Mary Anne Feakins.