Costello family involved in Holycross Murders 1827

I am trying to trace the lives of the father (Edmund), brother Edward and sisters Julia and Mary of Kate Costello who gave evidence in the trial of her first Keogh cousins, Thomas, Patrick and John, who were amongst those involved in the murder of Daniel Mara in 1827 near Rathcannon.

I know that the family sought refuge in Limerick and requested Gov't assistance for migration and I suspect they may have gone to America.

Any clues would be appreciated.

Margaret