When Polybius lost a brother in the early 40's, Seneca the Younger (then in exile) wrote his famous Ad Polybium in response. The intent seems to have been to gain Polybius' support for Seneca's recall to Rome. In the work, Polybius is praised for his loyalty to Claudius, but is also admonished that service to an emperor must come before grief. It had no effect on the freedman and Seneca remained in exile.
Disloyalty led Polybius to his downfall. He was executed for crimes against the state, proving that the freedmen were still in a position inferior to emperor, whatever their influence. Ancient historians claimed that Empress Messalina arranged for his death when she tired of him as a lover.