Willem was the son of Konrad van Alster and Marie de Hamal. The date and place of his birth have not been found.
His wife was Isaude de Dammartin. They were married, but the date and place have not been found. They had no known children.
Konrad van Alster |
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Jean de Hamal |
sir Guillaume de Hamal |
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Marie d'Oreye |
Guillaume d'Oreye |
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Johanna van Loon |
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