Their claim to the throne of Achaea came from her great - grandfather Philip of Savoy , eldest son of Thomas III of Piedmont and Guia of Burgundy .
Her maternal grandparents were Amadeus III , Count of Geneva and Mahaut d'Auvergne .
grandparents ' claim to the throne of Achaea came from her great - grandfather Philip of Savoy , eldest son of Thomas III of Piedmont and Guia of Burgundy .
Her maternal grandparents were Amadeus III , Count of Geneva and Mahaut d'Auvergne .