Just to make the search all the more interesting
I'm wondering about the three surviving daughters: Caroline Ann, Mary (Elizabeth) and Mercy. I know Caroline Ann was working for a family as a servant in 1881, and died ten years after; she was a spinster, aged 37. I don't know whether she had any children.
Mercy lost her mother in late 1881, and four years later gave birth to a son who died very young. She herself died aged 23 in early 1886.
As for Mary (Elizabeth), I would imagine she either died or married, which would explain why she isn't with her mother and sister in the 1881 and 1891 census entry. Is it possible to check her out, either as Mary or Mary E(lizabeth) Vickers/Vickress? Maybe she too was working in another household. There is a marriage in Dudley reg. district in Sep 1889 of a Mary Elizabeth Vickers and either Samuel Lunn (I think this would be her husband) or Joseph Potter. If she isn't on the 1891 census, maybe there's a Mary E. Lunn/Potter listed as having been born in Pensnett Staffordshire? As for her birth, I've had a look and there isn't a Mary Vickers who fits the census entry in 1861, but there's an Elizabeth born in Dec 1860 in Dudley (who would have been born as Henry's and Sarah's first child, a year after their marriage took place).
(Spidermonkey, I don't want to impose but you've been so helpful...)
