_Roger-Bernard II of FOIX _+
                                                       | (1195 - 1241) m 1208      
                              _Roger IV of FOIX _______|
                             | (.... - 1264)           |
                             |                         |_Ermessenda of CASTELLBO __
                             |                           (.... - 1237) m 1208      
 _Roger-Bernard III of FOIX _|
| (1243 - 1301) m 1252       |
|                            |                          ___________________________
|                            |                         |                           
|                            |_Brunissenda of CARDONA _|
|                                                      |
|                                                      |___________________________
|                                                                                  
|
|--Gaston I of FOIX 
|  (1287 - 1315)
|                                                       ___________________________
|                                                      |                           
|                             _________________________|
|                            |                         |
|                            |                         |___________________________
|                            |                                                     
|_Margaret of BEARN _________|
  (1245 - 1319) m 1252       |
                             |                          ___________________________
                             |                         |                           
                             |_________________________|
                                                       |
                                                       |___________________________