What is your evidence that John was born about 1839? There is no John of that age listed with his parents in the 1841 census, or any other John Davidson of that age who is not with other probable parents. He was 7 in 1851, and 18 in 1861, which is consistent with a birth in 1842/1844.
The evidence is just the ages on the 1851 census for Elizabeth Storrie of John being 7 and Elizabeth being 5 and as I said couldn't find a birth for John only an Elizabeth Story Davidson was born in 1846(spelled in many ways) and a Daniel Potter Davidson 1848 with parents William Davidson and Elizabeth Limeburn (er).
So there is no evidence to suggest that John Davidson, son of William Davidson and Elizabeth Limeburn(er), was born 5 years before 1842/1844, which is his approximate date of birth according to the census?
It looks as if no record of his birth/baptism have survived. This is not unusual.
As my ancestors are Daniel Potter and Helen Bolton (daughter of Elizabeth Storrie) thought it was too much of a coincidence for them not to be part of the same tree.
I agree.
do you think if I find the Janet Storrie who married Alexander Davidson father of a William Davidson's death certificate and find who her parents were and if it is William Storrie and Elizabeth Guy then she would be my Elizabeth's sister.
It's possible, but I did look for exactly that and did not find a death of that Janet Storrie.
The other alternative is to find evidence for John Davidson born 1844 perhaps his death certificate. What do you think?
I think I would try that, and also look for the deaths of his sister Elizabeth and brother William.
I have clutched so many straws in this branch of my family.
I am not suprised. They are proving a very hard nut to crack.
The simplest answer is that Elizabeth Storrie is also Janet Storrie, which would mean that somewhere along the line some clerk got her name wrong, but that is still in the realms of speculation.