Family Member 137 - Summary of Margaret Cowzer 1913

Parental Line

John Cowzer 1813
m.Anne Watts 1815
- Thomas Cowzer 1859
  m.Catherine Quinn 1862
  - Frederick Cowzer 1882
    m.Catherine Roache 1883
    - Margaret Cowzer 1913
      m.Frank or Derek

Summary of Margaret Cowzer 1913

Born : 1913
Partner :
- Name : Frank or Derek
Summary Tree :
None Known
Additional Notes :
I have two possible candidates for Margaret, an Essie or a Martha. Essie was mentioned by my father, and Ray has given me details for both an Essie and a Martha. Therefore I assume I have two individuals to fit into the family tree, but which one is Margaret, and then I need to add the other one. Maybe I can get help through this website?
Here are the details for both Essie and Martha (with some redactions) :
Essie m Frank O'N from Cork.
Frank and Essie had 5 children, Noel, Patrick, Charlie, Erin or Aran (girl), Nuala.
Martha m Derek H from Cabra.
Derek and Martha had 2 children, Seamus, Rory.
Rory m Patricia and had 3 girls, Martha, Sinead, Linda.