My 3x gr grandmother Maria Courtney born c1790 came from Belfast but do not know if she was born there as a baptism has not been found .... yet.
Maria was transported to Australia in 1818 along with her mother Margaret and Margaret's husband, Bernard Duffy (also convicts). Maria's sister Ann Courtney went to Australia with them.
I have not had much luck researching the Courtney name. There was a Susan Courtney who was also transported in the same year but she is not a close relative of Maria.