Jane Anne Franklin married 1st Capt. Richard Sherlock in 1835 , and then 2ndly she married a George Cashel Esq in 1839 and they lived for some years in Roselands Cottage, Listowel, Co Kerry. I believe this George Cashel was the eldest son of George Cashel Esq of Bedford House Co Kerry, and also of Shallee in Tipperary. Tipperary being his main home.
I think Tipperary would be a good place to start searching. When I did a little research on this family a little while back, I found that there were George Cashel, Cashell, Cashil , Cashills galore, and that Tipperary seemed to be where the 'seat' of the family was . I understood that in the early days, they owned mining land or rights there . Cashin could also be an earlier derivation of the name as well.
Good luck with your George's Laura !