_Giangaetano ORSINI _+
                                               | (1154 - 1232)       
                         _Matteo Rosso ORSINI _|
                        |                      |
                        |                      |_Oddo DI MONTICELLI _
                        |                                            
 _Gentile I ORSINI _____|
| (1200 - 1246)         |
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|                       |_Perna CAETANI _______|
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|
|--Orso ORSINI 
|  
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|_Constanza of UNKNOWN _|
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