Hi CaroleW,
Many thanks for your interest - it's much appreciated. I agree with what you say, and in a sense I'm already a step ahead of you - working in the opposite direction as it were

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I have already purchased the 2 birth certificates from the GRO. They show - not twins - but that sisters Mary and Ann both gave birth to illegitimate children within a few weeks of one another!
Margaret was born to Mary Davis on the 16th August 1843, with her sister Ann giving birth to Herbert on the 28th September 1843.
This is all part of a rather convoluted investigation I'm carrying out. This Davis family has proved to be difficult to trace through the various censuses, as family members change their ages willy-nilly, and professions also change. I've wondered many times whether I've got 2 or more separate families that I'm confusing - but always come back to the conclusion that no matter how strange it all sounds, my findings are actually correct.
Without going into too much detail here, I'm actually hoping to establish that the James Davis who is my 2x Gt Grandfather (and who married Sarah Ann Andrews at Claines, Worcs on 29th March 1840), was a brother to the aforementioned Mary and Ann - and also to further siblings Eliza (bap 7 Jan 1813), Samuel (bap 28 Jan 1821) and Elizabeth (bap 21 Feb 1830 - but born 1 May 1823). These children all have parents William & Sarah - with William being mostly a Bricklayer (with one baptism entry - Mary - putting him as a Mason).
James states on the Marriage Register that his father was William Davis - a Bricklayer. That's why I think he was part of this family - although I can't find his baptism. His death certificate says he was 65 yrs old when he died at Evesham on 4th March 1882 - so born around 1817. I'm working on the assumption that this family were a bit lax with their baptisms - note Elizabeth above - baptised when she was 6 or 7 years old - and Ann and Elizabeth were both baptised on 7th Jan 1813 - although I think they were also different ages.
Although I clearly can't be certain, what I've unearthed so far makes me think it is a strong possibility that James was born into this family around 1817 - but for whatever reason, was never baptised.
I originally thought that the James Davis baptised at Ombersley on 2nd Dec 1819 to William & Sarah was the person I wanted - but that William was a Labourer - and this couple had many more children at Ombersley.
Finding various grandchildren and children living with other members of this wider family over the various censuses have made me think I'm correct about James.
My next task is to try to establish the parents of the Sarah Ann Andrews who married James Davis in 1840. Helpfully, on the Marriage Register, she simply said her father was "Dead"

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I'm hoping that the fact that other family members can be traced living with Andrews families on various censuses will assist in this task.
Many thanks for those who have so far commented on this post - and I'm always open to further thoughts and suggestions.
David
PS - just to say this is an investigation I began way back, but never resolved at the time. After a long lay-off I'm having another go at it. A previous thread was posted here
https://www.rootschat.com/forum/index.php?topic=851715.0