Nan, along with her sister Patricia, ran Brennan's Criterion Bar in Bundoran for a lifetime, this famous pub opened in the 1900s by the Brennan family and in all those years remained more or less the same, run by the two famous sisters, it became a landmark place in Bundoran, where customers both local and visiting were always sure of a warm welcome. Nan, along with her sister Patricia, are regarded as highly esteemed members of the community.