_Gaston I of FOIX ___+
                                                       | (1287 - 1315)       
                            _Roger-Bernard IV of FOIX _|
                           | (1310 - 1350)             |
                           |                           |_Joan of ARTOIS _____+
                           |                             (1289 - 1349)       
 _Roger-Bernard V of FOIX _|
| (1330 - 1381)            |
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|                          |_Constance of LUNA ________|
|                            (.... - 1353)             |
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|                                                                            
|
|--Isabella of FOIX 
|  (1361 - 1428)
|                                                       _____________________
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|                           ___________________________|
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|                          |                                                 
|_Géraude of NAVAILLES ___|
                           |
                           |                            _____________________
                           |                           |                     
                           |___________________________|
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