_William of MOWBRAY _
                                            |                     
                       _Roger of MOWBRAY ___|
                      |                     |
                      |                     |_____________________
                      |                                           
 _Roger of MOWBRAY ___|
| (1254 - 1297) m 1270|
|                     |                      _____________________
|                     |                     |                     
|                     |_Maud of BEAUCHAMP __|
|                       (.... - 1273)       |
|                                           |_____________________
|                                                                 
|
|--John of MOWBRAY 
|  
|                                            _Gilbert of CLARE ___+
|                                           | (1180 - 1230)       
|                      _Richard of CLARE ___|
|                     | (1222 - 1262)       |
|                     |                     |_Isabel MARSHAL _____+
|                     |                       (1200 - 1239)       
|_Rose of CLARE ______|
  (1255 - 1316) m 1270|
                      |                      _John of LACY _______+
                      |                     | (1192 - 1240)       
                      |_Maud of LACY _______|
                        (1222 - 1288)       |
                                            |_Margaret of QUINCY _+
                                              (1208 - 1266)