Isabelle was the daughter of Pierre II de Grandson and Blanche de Savoie-Vaud. The date and place of her birth have not been found.
Her husband was Louis de Cossonay. They were married, but the date and place have not been found. They had no known children.
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Pierre II de Grandson |
Jacques de Grandson |
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Richard de Neuchâtel |
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Marguerite de Montfaucon |
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Blanche de Savoie-Vaud |
Louis I de Savoie-Vaud |
Tomaso II di Savoia |
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Béatrix di Fieschi |
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Jeanne de Montfort |
Philippe II de Montfort-Castres |
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Jeanne de Lévis-Mirepoix |