Catherine Ann Atkinson married William Breer Johnson in Thomastown, Kilkenny, in 1852: they are my ggg parents.
Her elder brother William Atkinson married first Penelope (Price) Ronayne, widow, in Youghal in 1855 ; and second Elizabeth Clifford, in Waterford in 1887.
I do not find, nor expect to find, these Irish images online.
Her younger brother Moorsom Atkinson married Elizabeth Garrow in 1854 in Dodbrooke (Devon) -- as mentioned above he recorded his father as “Capt William Atkinson RN” : at least that's what the newspapers said at his bigamy trial.