On her son’s death certificate her maiden name is clearly given as Charteris but for marriage and the birth of her daughter Janet she was Charters.
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Other births to her and John Turner:

                         Fore                                             City/
No  Date        Surname  name   Parent Names Frame No. Sex Parish        County     GROS Data
1   13/07/1813  TURNER          JOHN TURNER/               DUMFRIES    /DUMFRIES  821/00 0070 0194
2   13/01/1811  TURNER   JANET  JOHN TURNER/            F  LOCHMABEN   /DUMFRIES  840/00 0010 0196
                                      CATHERINE CHARTERS    
                                           FR109 (FR109)
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The following could be her in the 1841 census but she would have been only 15 at marriage, though she would have been up to five years older than the recorded age in the 1841 census:

First name(s) Last name Gender Age Birth year  Birth place

Catherine  Turner     Female  45  1796  Dumfriesshire, Scotland
Jane       Turner     Female  25  1816  Dumfriesshire, Scotland
Robt       Turner     Male    15  1826  -
William    Turner     Male    15  1826  -
James      Turner     Male    15  1826  -
Isabella   Henderson  Female  15  1826  Dumfriesshire, Scotland
Census details
Family member first name  ISABELLA, JAMES, WILLIAM, ROBT, JANE, CATHERINE
Family member last name   HENDERSON, TURNER
First name(s)             Catherine
Last name                 Turner
Gender                    Female
Age                       45
Birth year                1796
Birth county              Dumfriesshire
Birth place (other)       Scotland
House name                Millmeadow Cottage
Street                    Millmeadow Cottage
Parish or township        Moffat
County                    Dumfriesshire
Country                   Scotland
Occupation                Ind
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And this, with the Johnstone birth in 1791, must be her in 1851, though the birth of her son Robert in the USA is surprising:

First name(s) Last name Role Marital status  Gender  Age  Birth year  Occupation  Birth place
Catherine  Turner     Head  W  F  60  1791  Annuitant             Johnstone, Dumfries, Scotland
Robert     Turner     Son   U  M  29  1822  Proprietor Of Houses  United States
Mary       Nicholson  Serv  U  F  20  1831  House Servant         Moffat, Dumfries, Scotland
Jane       Johnstone  Ldgr  U  F  63  1788  Annuitant             Moffat, Dumfries, Scotland
Alison     Gillespie  Vstr  U  F  21  1830  -                     Douglas, Lanarks, Scotland

Census details
First name(s)          Catherine
Last name              Turner
Role                   Head
Marital status         Widow
Gender                 Female
Age                    60
Birth year             1791
Occupation             Annuitant
Birth place            Scotland
Birth town             Johnstone
Birth county           Dumfriesshire
House name             Rosemount Cottage
Street                 Rosemount Cottage
Parish                 Moffat
County                 Dumfriesshire
Hamlet                 Moffat
Registration district  Annandale
Record set             1851 England, Wales & Scotland Census
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In 1861 she was living with a farming (700 acres) family of Williams, b. 1803, and Grace, b. 1806, Scott, with Grace too being born in Johnstone, so I wonder if she was a relative.

Not in the 1871 census but no death can be identified in Scotland from 1861 to 1891.  In Britain as a whole there were 191 deaths, so quite impossible.

In 1871 the Scotts were still farmers, now with 1000 acres.  But no Catherine Turner.

No will found for her either.
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Their marriage register records for Lochmaben parish in 1809:

John Turner in this parish and Catherine Charters from the parish of Johnston had the banns of marriage three time regularly published befor the Congregation & no objections being offered they were married accordingly on the 12th day of Decr.
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