Guillemette was the daughter of Jean le Mercier and Jeanne de Saint-Dizier. The date and place of her birth have not been found.
She had two marriages/partners. Her first husband was Jean III de Chepoy. They were married, but the date and place have not been found. They had no known children.
Her second husband was Renaud de Coucy. They were married, but the date and place have not been found. They had no known children.
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Jean II de Saint-Dizier |
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Alix de Clermont-Nesle |
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