As William Blackford and Ann nee Martin did not have an Elizabeth WESTON as a child, Especially not at the time of William's own birth, I am checking out records for Elizabeth Weston becoming a Blackford.
I have come up with two referencing the same record, Which fits a few theories
When you searched for:
First Name
ELIZABETH
Last Name
WESTON
Exact Match?
Yes
Start Year
1750
End Year
1800
Record Type
Marriage
https://www.freereg.org.uk/search_records/581869e3e93790eb7fc12022/...
and
https://www.freereg.org.uk/search_records/581869ede93790eb7fc133dd/...
As such, I am appropriating this profile, away from William Blackford.