After the murder of his father Pavle Radinović (died 1415) on Parena Poljana near royal court in Sutjeska and below a Bobovac in 1415, after the stanak at which whole Pavlović family was present at, Petar took over the leadership of the Pavlovići and with his younger brother Knez Radosav (1420–1441) started a war against Sandalj Hranić (1392–1435) and Kosača klan.

During a morning walk on August 24 on Parena poljana, the members of Zlatonosović's, at a signal given by Grand Duke of Bosnia, Sandalj Hranić himself, attacked Knez Pavle Radinović with a sword and seriously wounded him.

As a witness to this attack, Petar directly blamed Sandalj for the death of his father, which pushed the entire south-eastern part of today's Bosnia and Herzegovina into a war between Pavlović on one side and Hranić clan, on the other.

Petar asked the Ottomans for help in this conflict, promising them vassalage in return, which they accepted, and already in the fall of 1415, their detachments invaded Hum led by the brothers Đurađ and Stjepan of Bosnian Vlach tribe of Miloradović.

[3] Pavlović's pressure on Sandalj and those who supported him was so great that the King Ostoja himself had to secretly escape at night from stanak, the meeting of the Kingdom's nobility, in order not to suffer the same fate he had organized for Pavle Radinović a few years earlier.

[3] The conflict between Pavlović and Kosača itself subsided over time, while both families practically disappeared during the Ottoman conquest of Bosnia and Herzegovina, which was a prolonged process stretching over 50 years, between 1463 and 1528.