Пуэбла-де-Сарагоса
Lefebvre has been involved in politics, with the Parti Québécois (PQ), since the age of 17. Following her bachelor's degree in political science at Université de Montréal, her studies took her to the Universidad de las Américas in Puebla, Puebla, Mexico. There she gathered much political experience, notably as an intern at the Quebec Government House in Mexico City and as parliamentary assistant to French politician Philippe Séguin.