Titus Flavius Sabinus was a tax-collector and son of Titus Flavius Petro, who had been a centurion during the Civil Wars on the side of Pompey. During the wars, Petro fled from the field of battle and had to obtain pardon. Vespasian's older brother, Sabinus, rose to the rank of Prefect of Rome. The sons of Domitilla the Younger, Vespasian the Younger and Domitian the Younger, were adopted by Domitian as his heirs. However, their father, Flavius Clemens was executed in AD95, and the subsequent fate of the two boys is unknown.

                                                                                  Ti. Flavius Sabinus = Vespasia Polla
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                                                        Sabinus                                                   Vespasian = Flavia Domitilla
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                                    Titus = Marcia Furnilla                   Domitian = Domitia Longina                  Domitilla = Flavius Clemens
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                                      Julia Titi = Flavius Sabinus                                                                        Vespasian                               Domitian
                                                                                                                                                                the younger                          the younger