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Prince Pinklao was the eldest surviving son of King Rama II. He was also the half-brother of King Mongkut, who succeeded their father to the throne in 1851. During Mongkut's reign, Prince Pinklao was crowned as Second King, a position that had been abolished by King Rama I. As Second King, Prince Pinklao served as Mongkut's deputy and helped to administer the government.