Prior to her entrance into provincial politics Sullivan had a 30-year teaching career and was the Deputy Mayor of Grand Falls-Windsor.
She received her Masters of Education from Mount St. Vincent University, in Halifax, as well she was awarded a French immersion diploma from Université Laval, in Quebec City.
[2] In June 2007, Sullivan defeated two others to win the Progressive Conservative Party nomination for the district of Grand Falls-Windsor-Buchans.
[7] In the October 11, 2011 provincial election, Sullivan was easily re-elected as the member of the House of Assembly (MHA) for Grand Falls-Windsor-Buchans.
[11] When Paul Davis took over as premier in September 2014, Sullivan was appointed Minister of Education and Early Childhood Development.