His elder sister Veronica [it], on the other hand, was married to the Florentine nobleman Jacopo Salviati, but was involved in an obscure episode in 1633, when she was alleged to be behind the savage murder of Caterina Brogi, Jacopo's mistress, whose head was delivered to him in a basket.

Veronica was repudiated by her family, but their pressures on Medici government managed to prevent her being prosecuted for the murder.

She was forced to leave Florence and to retire to the countryside, near Figline, in the Salviati's Villa San Cerbone [it].

[4] To pursue his ecclesiastical career, Cybo went to Rome in 1641, as Domestic Prelate and as a referendary of the Tribunal of the Two Signatures to Pope Urban VIII.

[5] On 6 March 1645, Cybo was elevated to the rank of cardinal by Pope Innocent X, and named Cardinal-Priest of Santa Pudenziana.

On 6 February 1679 Cybo was appointed suburbicarian Bishop of Palestrina by Pope Innocent XI.