William Couche 1810/3-1849 and Ellen Crone Baldwin St Brigown Mitchelstown Cork

I have traced my William Couche and Ellen Crone through  a reference to their marriage in 1837, in St Finbars Cork South Cork and Ross, noted in the Casey volumes on Ancestry but coudl find nothing about their i children although they lived in Baldwin St Brigown Mitchelstown Cork when they died  The only other William Couche that may be relevant wa sborn in 1813 in Gosport Alverstroke Hampshire also born to a William and Ellen. I woudl like to apply for their marriage certificate but need some advice on where to get it 

I found an Ellen Couch 1782-1876 in Clare cemetary who woud fit this couple DOB but nothing else. Ellen's son Richard Couche also married a Margaret Crione Buttevant Cork parents Honoria Roache and Thomas Crone Peerage pages I suspect Ellen Crone may be THomas sister parents Richard Crone and Elizabeth Browning.

Richards and Margaret Crone Couches first four children died when he and margaret Couche were in Victoria and they went back to Brigown Mitchelstown to live in their mothers house having 11 more children. Ellen Constance Crone 1869, dying just after her birth in Brigown, after they arrived back from Auistralia.

 I wondered if the names of their  children  might help  give  a clue as to her Margaret Crone Couches mother Honora Roache true name and also Richards father and mother also.  Two of these became famous photographers Jeffrey Couche  and Claire Patrick Couche died in WW1 as a photographer war correspondent Could someone help me here  Richard Couche and Margaret Crones  children were:

Thomas COUCHE ( - 1865)
Eliza Anne COUCHE (1864 - 1864)
Christopher William COUCHE (1865 - )
Martha Ethelind COUCHE (1866 - 1866)
Ellen Constance COUCHE (1869 - 1869)
Ethil (Ethie) COUCHE (1870 - )
Caroline Crone COUCHE (1870 - 1952)
Adelaide COUCHE (1872 - )
Aphra Crone COUCHE (1873 - )
Emma COUCHE (1875 - )
Jeffery Crone COUCHE (1876 - 1936)
Victor William COUCHE (1879 - 1943)
Christine COUCHE (1880 - 1953)
Richard George COUCHE (1882 - 1947
Clara Browning COUCHE (1884 - 1956)
Clair Patrick COUCHE (1886 - 1918)

Many thanks I have hit a brick wall. Any help would be much appreciated

Jeanne Solity