Prince Keofa, aged 11, mounted the throne. King Keofa was murdered and some believed that he was poisoned by Khun Worawongsathirat who was Thao Sisudachun’s lover. Prince Sisin, aged 7, became the king with Worawongsa acting as Regent. Later Worawongsa became king for forty two days but “being a usurper, he has not been counted as one of the kings of Ayutthaya.” (Rong Syamanada 1993 : 47). Worawongsa and Sisudachun were killed by Khun Pirenthorathep and his party. Then they invited Prince Thienraja who was Chairaja’s brother to leave the monkhood to mount the throne and he was named Mahachakraphat.