Complex sentence: Her paternal grandparents were Amadeus VIII of Savoy, who was also the Antipope Felix V, and Mary of Burgundy, and her maternal grandparents were King Janus de Lusignan of Cyprus and Armenia and Charlotte de Bourbon-La Marche.
Split into simpler sentences: Her paternal grandparents were Amadeus VIII of Savoy, who was also the Antipope Felix V, and Mary of Burgundy. Her maternal grandparents were King Janus de Lusignan of Cyprus and Armenia and Charlotte de Bourbon-La Marche.