Have you looked in the Paisley Poor Law Index for any Cathcarts or Caldwells that may be the family?
I see there is a 'Widow Cathcart', husband Walter, listed.
Series 12, statement number 6196.
This index does not give the date for this entry.
The index starts in 1839.
There is also a Charlotte Caldwell listed.
Series 12, Statement number 5733
Again no date for this entry.
Paisley Heritage Centre are very helpful.
They can send you a precis of an entry.
I think the entries are compiled from different indexes, so some of them give more information, and some less.
If you Google Paisley Poor Law Index, you can download the whole pdf of the indexes.
You will see there are quite a lot of Cathcarts - perhaps some of them are the children of Walter, you never know.
You can find a wealth of information in the records if you're lucky.
I know I managed to break one of my huge brick walls of many years when I finally found an application in these records - and again it was by chance, as she was indexed as 'widow Paton'.
It gave me lots of great information about her and her husband's family.
Good luck
