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October 21 marks the commemoration of Srinagarindra's birthday in Thailand. Srinagarindra, also known as Princess Mother Srinagarindra, was the mother of King Bhumibol Adulyadej, the revered late monarch of Thailand. This day serves as a significant occasion to honor and celebrate her contributions and devotion to the nation. The date holds deep cultural and historical importance, reflecting Thailand's profound respect and gratitude for the royal family's dedication to their country.