1851 Census
Patrick
Ballacosnahan
Robert Clark head married 34 ag lab b Malew
Cath wife married 34 b Malew
Elizabeth daughter 9 b Malew
Cath daughter 8 b Malew
Ann daughter 5 b Malew
Eliza daughter 3 b Malew
Ellen daughter 9mo b Malew

1861 census index notes Robert is 43 b Santan

Patrick Burial Record
Catherine Clarke age 40 buried 23 Nov 1856

Perhaps this is your Catherine

I'm not sure which Caine line she belongs to.

I don't see a Robert Clarke b in Santan