Going backwards from birth

My great-grandmother Fanny Welch, née Tipton was born on 21 September 1879.  The registration was in the Sub-district of Walsall, in the County of Stafford and the family's residence was 36 Oxford Street, Pleck, Walsall (see 1885 map).  The birth certificate names her parents as Henry Tipton and Lydia Tipton, formerly Cox.

Going back to that generation, there was a marriage between Henry Tipton and Lydia Cox about five-and-a-half years before Fanny was born.  The wedding took place on 31 January 1874, at the Register Office in the District of Walsall, with Henry age 21 and Lydia age 19.  To take us back another generation, the marriage certificate names Lydia's father as William Cox, Herbalist.  So can we find her mother, too?

If we assume firstly that Lydia's age was correct on the marriage certificate, secondly that she was born in Staffordshire, and thirdly that she was not called by some other name as a baby, then there is one plausible birth registration from amongst many in the FreeBMD search results.  The GRO Online Index gives the mother's maiden name as Boffy.  However, with so many assumptions it would be helpful to find some supporting evidence that we are focusing in on the correct family.

Next we could look for a marriage between William Cox and a woman with that surname.  The good news is that in all the years and all the country there seem to have been only two such marriages.  The bad news is that both of them happened within six years and six miles of one another.

• William Cox and Harriett Buffey married in 1843, in St Matthew's Church Walsall.
• William Cox and Mary Boffey married in 1839, in St Martin's Church Tipton, in the Dudley district.

What is more, each of those couples named a daughter Lydia Cox!  Also, each family had children named William and Mary and Harriet.  Amazingly, both families lived initially in the West Bromwich district and both moved to Pleck, Walsall by the 1861 census.  Altogether, during twenty years there were at least twenty children born with the surname Cox and mother's maiden name spelled variously as Boffey, Boffy, Botty and Buffy (GRO Online Index transcription).  So who belonged with whom?

In the 1871 census, three years before Lydia married Henry Tipton, one William Cox is a Labourer but the other William Cox is recorded as being a Herbalist and he is in Oxford Street Walsall.  At home with him are his wife Mary and five children, including Lydia age 16.  With that specific, unusual occupation, as well as the address and the expected age for Lydia, we seem to have strong enough evidence to place Mary Boffey on the pedigree chart.