He often deals with the beauty of women, a subject which eventually led to disaster in real life.
Thammathibet and his half-brother Chao Sakaeo (Prince Sunthon Thep) had an argument about an elephant.
In April, 1746, Thammathibet reportedly laid siege to the palace of his half-brother, forbidding any entrance or exit.
During the further interrogations, Thammathibet confessed that he had visited four of the numerous royal concubines and planned to assassinate his father the king and his family and seize power in Ayutthaya.
The king gave an order to give Thammathibet fifty more blows and burn his forehead, arms, and legs.