Suleiman the magnificent had five shehzade. But, in the struggle for the throne, there was only one - the quietest, meanest and drunkard.
Bayezid in a fair battle had the opportunity to take Selim's life, but could not. And this was one of the main mistakes.
After Bayazid, together with his four sons and loyal warriors, was forced to take refuge with the worst enemy of the empire of the Shah Tahmasp, and this was another mistake that later led him to execution.
Shah Tahmasp suggested Bayazid to unite and go against the sovereign, but Shehzade refused. He will never betray his father, even knowing that he signed the order for his execution.
Suleiman is no longer so young, and the shah understood that he would not be able to go to his domain with an army, therefore, from this situation, he decided to profit.
The ruler was ready to pay a considerable sum for the life of his son, but Selim offered twice as much, and the shah gave the shehzade to his brother.
The scene of the execution itself is very difficult. Selim promised Bayezid and his sons to give life if he asked for mercy. But Bayezid knew perfectly well the nature of his brother, and that he never keeps his word, so he spat at Selim with curses.
The elder Shehzade Bayazid was also surprised by the moment, he gestured to his father that he should not trust and ask for mercy. Bayazid's children behaved courageously and proudly, despite the sadness of the event.
Selim eliminated the last competitor to the throne, he did not give Bayezid the opportunity to meet with his father, because he understood that the sovereign could pardon him.
He did not spare either his brother or nephews. The lust for power has covered the mind. Selim is one of the sons who did not have a sense of compassion and mercy, and this is what led him to the throne.