Thailand’s revered monarch, 87-year-old King Bhumibol Adulyadej, and his wife, Queen Sirikit, are both in declining health and have been absent from public life for years. Their only son and the heir apparent, Crown Prince Vajiralongkorn, does not command the same respect and affection as his father, though open discussion of the monarchy is constrained by a strict lese-majesty law that makes criticism of the royal family punishable by up to 15 years in prison.