Not only was she his father Amadeus' first cousin, in such a way that her rights would naturally descend to this line, but also she was the widow of Charles's paternal uncle Louis of Savoy, Count of Geneva (d.
Nejen že byla sestřenicí jeho otce Amadea, takže její práva přirozeně sestoupí do této linie, ale ona byla také vdova po Karlovu strýci Ludvíkovi Savojském, hraběti ze Ženevy.