Frances Eleanor Keegan was born on October 15, 1896, in West Newbury, Massachusetts, the third daughter among the four children of John L. Keegan and Margaret E. Costello.<ref name=1/30/1943Globe></ref><ref name=2/8/1943WaterlooCourier></ref> Her parents were first generation Irish: the Costellos from Tipperary and the Keegans from Kildare.<ref name=2/2/1943CourierJournal></ref> John Keegan had a career as superintendent of machine tool manufacturing.