I wasn't convinced that Catherine is Kate either but checking further that death may be the wrong Roger Bevan.
He's one in 1911 who is a painter with wife 'Cathern' & married 10 years- same address as death in 1913-
http://www.census.nationalarchives.ie/pages/1911/Cork/Cork_No__4_Urban__part_of_/Blarney_Street/390162/
Marriage of that Roger Bevan to Catherine O'Neill in 1900 rules that one out-
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1900/10349/5767558.pdf
Back to searching for deaths of Roger & Kate 
Think I may have found death of roger but still can't find kate's.
Name Rodger Bevan
Birth Circa 1877
Death Mar 6 1917
Age at death 40
Burial / Commemoration Faubourg D'Amiens Cemetery, Arras, France
Burial Notes V. G. 20.
Rank Private
Regiment Royal Munster Fusiliers
Unit / Ship B Coy. 1st Bn.
Service # 9/5417
Father
Name: Maurice Bevan
Residence: Cork
Mother
Name: Mary Bevan
Residence: Cork
Spouse
Name: Kate Bevan
Residence: 21, Peter St., Cork
Comments Son of Maurice and Mary Bevan, of Cork; husband of Kate Bevan, of 21, Peter St., Cork.