If you haven't seen the birth certificates, I assume you got the dates
from censuses. It is possible, and even quite likely, that Anne is a
daughter of one of Ann's children - maybe John, but more likely a
daughter you don't know about.
In one of my families there was a child who was believed to be a
daughter in one census, until we found her listed as a granddaughter in
another - it turned out she was the illegitimate daughter of the eldest
daughter. She lived with her grandparents until they died, even though
her natural mother had married and had other children, and could have
brought her up - but perhaps her husband didn't want another man's child
in the house. It was only last year when I spoke to a niece of this
child (now an old lady of about 80) that it was confirmed who her mother
was.
In another case, in the 1851 Census, I found my great grandfather, aged
2, listed as the nephew of the head of the household, along with his
mother, who was listed as the daughter! And in this case the child was
not illegitimate, but his parents had been legally married and he had
been baptised, but I think his mother had run away from his father. It
remains a total mystery! But the moral of this story is that you can't
believe all you read in censuses! Apparently in this case the
relationship of "nephew" had been invented to explain why the child had
a different surname - his mother was listed under her maiden name. For
whatever reason, people not infrequently gave false information to the
census enumerator.
Apart from this, it would not be impossible for a woman of 53 to have a
child, it is just that the granddaughter explanation is much more
likely.
Re the possibility of Ann having been married to someone else before
David Jones, I don't see any reason for this. David would have been 22
when John was born. The fact that John was born in Ann's home parish may
reflect the fact that the young couple were staying with the wife's
family (I have seen this before) or simply that Ann, like many other
women, had gone to her mother's for the birth of her first child. If Ann
was a midwife, it is highly probable that she had learned this skill
from her mother, so where else would she go to give birth? I will try to
remember to ask my Welsh teacher about words for midwife next time I see
her.
Best wishes,
Ann
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Ann Macdonald Watt
Edinburgh
Scotland
email: ann(a)met.ed.ac.uk
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