Through Moore she was introduced to a number of prominent figures in the Irish literary revival, and also worked for the publishing house, Maunsel and Roberts.
She joined the office staff of Sinn Féin in their headquarters at 6 Harcourt Street, Dublin in 1917 and continued working in various roles including the Propaganda/Publicity Department until long after the end of the Irish Civil War.
She later served as a secretary to Michael Collins, preparing briefings for foreign correspondents, typed and mimeographed the news sheet of the Dáil department of publicity, and assisting in the collating and composing Irish Bulletin from 1919 to 1921.
She was imprisoned in Mountjoy, then Kilmainham where she went on hunger strike, and then the North Dublin Union from which she escaped with a number of fellow female prisoners, but was rearrested in May 1923.
She was a roving reporter in the southern counties, writing a popular series of wry profiles of villages and towns in the early 1930s.
Kelly would travel to Geneva frequently to cover meetings of the League of Nations, working as an informal aide to de Valera's Irish delegation.
[1] During the Big Freeze of 1947, Kelly visited a tenement district in Dublin to stand in a fuel queue to report first hand the suffering of people in the unusually cold weather.
"[6] During the truce, she married a fellow member of the Sinn Féin headquarters staff, Francis M. Kelly known as Frank, on 23 July 1921.